Occup. Med. Vol. 50, No. 7, pp. 483-491, 2000Copyright © 2000 Lippincott Williams & Wilkins for SOM

Printed in Great Britain. All rights reserved0962-7480/00

IN-DEPTH REVIEW Ageing and fitness to workG. Chan,* V. Tan1 and D. Koh*^Republic of Singapore Navy, Headquarters SAF Medical Corps, Singapore;^Johnson & Johnson Pte Ltd, Singapore; and *National University of Singapore

Ageing workers can be found in almost all occupations. Assessment of fitness to work inthese workers is important, as it aims to match their functional capacity (which isreduced compared to younger workers), to the demands of their work (which mayremain the same as that for younger workers). This outcome of assessment isinfluenced by the interaction between functional capacity, state of health, the nature ofwork, and possibilities for work accommodation. The assessment of functional capacityshould include physical, mental and social capacity, as well as assessment of anydisability. In addition to clinical or laboratory measurements, several authors havesuggested the use of a 'work ability index' for specific occupations as a practical meansof selecting the appropriate worker for the job. This index can also be used formonitoring functional capacity. In addition, as for any fitness to work assessment, agood understanding of the nature of the work and the work environment is required, andpossibilities for work accommodations considered. While changes in the workenvironment and working conditions can be made to suit the functional capacity of theageing worker, the maintenance of functional capacity is another important issue. Thereis a place for a greater role for disease screening and health promotion for suchworkers.

Key words: Ageing worker; fitness to work; functional capacity; work ability.

Occup. Med. Vol. 50, 483-491, 2000

INTRODUCTION

There is a general trend toward 'ageing' in thepopulation of both industrialized and developing coun-tries, as a result of longer life-spans and decreasedfertility rates.1 A corresponding increase in the propor-tion of ageing people in various occupations is alsoobserved.2 While an estimated 32% of workers were inthe age group between 45 and 60 years of age, therespective percentage will be 35.5% in the year 2000, and41.3% in the year 2010.3 Such a trend is particularlymarked in Asia; in Japan for instance, three-quarters ofthe male population between 60 and 64 years of age arestill in the labour force.3'4

Ageing workers can be found in almost all types ofoccupation. Work demands and working environmentsare not necessarily different for ageing and youngworkers, and more often than not, are quite similar.Assessing fitness to work in the ageing worker is thusassociated with a number of health, social and ethicalconsiderations.3'5

Correspondence to: Major (Dr) Gregory Chan, Head Preventive MedicineBranch, Headquarters SAF Medical Corps, 72 Loewen Road, Singapore248843, e-mail: prevmedjiqmc® medscape.com

MORE THAN JUST A MEDICALEXAMINATION: THE CONCEPT OF'PRODUCTIVE AGEING' AT WORK

Ageing workers constitute a special group in the labourforce, with characteristics that require special attentionfrom the occupational health point of view. One of themain problems in ageing and work is the incompatibilitybetween the functional capacity of the worker and thedemands of the job. The work demands do not usuallyincrease with time but work capacity usually decreaseswith age.6'7

A 'fitness to work' assessment for the ageing worker ismore than just a medical assessment: it requires that thephysician understands the nature (work hazards andstressors) of the job, and has the ability to makerecommendations for job redesign (the concept of'age-adjusted workload').6"8 It also involves an under-standing of the physiological changes in ageing andfunctional capacity of the individual, and would be anopportunity to promote health factors and prevent ill-health (the concept of 'maintaining functional capa-city').9'10

The concept of 'productive ageing', as described byIlmarinen et al., is based on the principle that workdemands should change, just as workers themselveschange as they grow older.3'11>12 It should be emphasizedthat a number of mental and social abilities can undergoa positive change with increasing age, and such new

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484 Occup. Med. Vol. 50, 2000

strengths should be respected and exploited in everydaywork.8'13'14

FUNCTIONAL CAPACITY AND ITSIMPLICATIONS AT WORK

Human functional capacities change with age. The levelof functional capacity, both within a single individual andamong individuals belonging to the same age group, ishighly variable. It is not clear when these changes occur,but it is generally accepted that physical capacity starts todecline first, and at a faster rate when compared tomental or social capacities.3'15 The start of decline is setarbitrarily at 45 years of age by the World HealthOrganization (WHO). It is worthwhile mentioning that asmall but significant portion of the working population isin the elderly age group (above 60 years) and geriatricage group (above 65 years).3'4 These categories ofelderly workers will benefit greatest from a completefunctional assessment.16

In addition to the possibility of reduced job produc-tivity, the decrease in functional capacity with ageing hasthe following work-related implications.

have limitations that may affect their adaptability in someways, they can generally learn; the difficulty sometimesarises when they are taught using techniques meant foryounger workers.6'26'27

Job performance

Although performance deteriorates with age in situationswhich place high demands on cognitive functions, suchas sensory and perceptual activities, selective attention,working memory and swift information processing, olderworkers have at least similar productivity rates for taskswhich require experience and expertise.28 It is alsoobserved that there is a steady increase in consistency ofjob performance from those of 25 to 60 years of age.29

General work effectiveness

Older workers tend to exhibit a lower rate of staffturnover. They may also have specific strengths, such asa greater dedication to work, better routine skills, a morestable character due to experience, and age-relatedintellectual and personality development, which makesthem suitable for certain demanding jobs.13

Accidents in the workplace

A decrease in functional capabilities has been blamed forsome of the workplace accidents to the elderly.17

However, a comparison of workplace accidents betweenthe ageing worker and the younger worker has remainedcontroversial; some studies have not shown any signifi-cant difference in the accident frequency, while othersshowed fewer accidents in the older worker.18'19 It isgenerally agreed that the injuries sustained by the olderworker tend to be more severe.20 Older employees werealso less willing to return to work after an accident.21

Absenteeism

Absenteeism rates usually increase with age but itscharacteristics differ from those of younger workers.22

Sickness absence is due largely to chronic disease,resulting in chronic sick leave of longer duration.23 Incontrast, the younger worker usually has recurrent,short-term sick leave and there are often strong non-medical reasons for such absenteeism.24

Job restrictions

The ageing worker may need to be reassigned away fromsome jobs, such as those with exposure to severe thermalstress, heavy and continuous effort, and enforced highwork rates, and toward those that are more appropriatefor reasons of work productivity and safety.3

Adaptability

Adaptability could be described as the ability to learnquickly, to grasp new ideas, to adapt to change and havethe interest to be trained.25 Although older workers may

ROLE OF A FUNCTIONAL ASSESSMENT

Assessing functional capacity, whether physical, mentalor social, requires one to 'peg' at the level of functionalcompetence required for the specific job. A particularsystem may be more relevant than others, and it maythus be easier for the physician to break down the workscope into the relevant systems involved.30'31 Forexample, a physically demanding job requires anassessment of one's physical capacity, which couldinvolve one or more of the following: physical bodycomposition, musculoskeletal capacity, cardio-respira-tory capacity, sensory organs, central nervous systemand coordination. Mental capacity could require assess-ments of memory function, intelligence and ability torespond to safety. Jobs that need both physical andmental abilities may require assessing a mixture of theabove systems.

ASSESSING PHYSICAL CAPACITY

Eyesight: visual capacity3'32'33

Accommodation acuity is decreased and presbyopianecessitates the use of reading glasses. There isdiminished tolerance to glare sensitivity with slowing ofadaptation to darkness, and colour discrimination isimpaired. Close work and that involving accuracy, suchas the assembling of electronic components, andrepetitive quality checking, may be adversely affected.Adequate illumination while minimizing glare at work isthus important. There may also be concomitant diseasessuch as cataracts and age-related maculopathy, whichcan affect vision. Vision is important in workplace safetyand thus should be part of the functional assessment.15

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G. Chan et a/.: Ageing and fitness to work 485

Ears, and hearing capacity3'32'33

The phenomenon of presbyacusis, in which speech isdistorted due to poor quality amplification, may befound in the elderly. The problem may be aggravatedby working in a noisy environment, especially in jobsthat demand concentration. Communication difficultieshave safety implications and may lead inadvertently tosocial isolation for the elderly worker. Sometimes,degenerative changes in the inner ear can also affectbalance control.15

Musculoskeletal system: strength and coordinationcapacity3'32"34

Loss of skeletal muscle results in decreased lean bodymass. There is thus an increase in the ratio of fat tolean body mass. Muscular strength declines with age,with the rate of decline accelerating at about the age of50 years.35 Handling heavy materials is less welltolerated by older workers due to lower musclestrength and degenerative joint disease, and may leadto injury and accidents.36 Prolonged periods in anawkward position may also be less tolerable and mayaccelerate damage in joint tissue. There may also bediminished bone density and neuromuscular coordina-tion. Speed and reaction is thus reduced; furthermore,repetitive jobs are more likely to lead to musculoske-letal disorders.

Examination for joint deformities, muscular atrophyand asymmetry is useful as they will have an effect onmobility, such as in a case of osteoarthritis of theknee. The site of the affected joint, whether it is inthe upper or lower limb, or is of single or multipleinvolvement, will have an impact on the level ofdisability.15'37"39

Cardiorespiratory system: aerobic capacity

The cardiorespiratory system undergoes a number ofchanges with ageing including a reduced cardiacoutput, decreased maximum breathing capacity andmaximum oxygen uptake during physical exertion(reduced by about 60% between 30 and 70 years ofage).40'41 These changes can contribute to decreasedeffort tolerance. According to the 'stress-strainconcept', in heavy physical work, maximal cardio-respiratory capacity determines the level of strain. Thebetter the maximal oxygen consumption (Kc^max),the lower is the cardio-respiratory strain at a givenwork load.38

Posture control: balance capacity

The elderly are unable to regain their balance quicklywhen tripped.14'32 Hence they are prone to frequent falls.Education of the worker, fellow workers and employer inhazard awareness at the workplace is essential for theageing workers' safety. Posture control can be tested byobserving the amount of postural sway when standingupright with the eyes closed.

ASSESSING MENTAL CAPACITY3'32'44

Age-related physiological changes that occur in percep-tion, information processing, and motor performancemay weaken most parts of an individual's mentalcapacity.13 Psychomotor performance is slower andintellectual performance is decreased. Recent memoryis impaired. Reaction time is also slower. Theseworkers may also be slower in complex learning.45

Training an older worker in new skills may bechallenging and the methods used may have to differfrom that of a younger worker in that it should bemore 'practically' based.46

Assessing mental capacity is not a tedious process.The underlying principle is that the mental status of aworker will not compromise the safety of self or others atwork. It should also be commensurate with the ability toperform the required tasks. In general, the physicianshould assess the following.

• The ability to understand and perform work,• the ability to follow instructions,• the ability to communicate and interact.

Mental state examination scales are available and areuseful screening tools for the assessment of the worker'spsychological state, although there have not been studieswhich compare the reliability between scales for theworking aged. The physician should try to be familiarwith at least one type. The one that would be most usefulwhen used for an elderly or geriatric individual is thatwhich screens for cognitive function and depression.47'48

Examples include the Abbreviated Mental Test, and theMini-mental State Tests.14'33

ASSESSING SOCIAL CAPACITY

A social assessment is an integral part of the overallfunctional assessment of the older adult. It provides thesocial and emotional context of the individual, therebyinteracting with physical and mental health, as well aswork ability. It should include the physical environment(e.g. physical living and working conditions, safety), aswell as the financial situation, social and communitysupport system, psychological and emotional health andfamily dynamics.14'31

A basic framework for functional capacity assessmentis shown in Box 1. This could be combined with Box 2 toform a more complete checklist for the examiningphysician.

It can be seen diat physical potentials, such asaerobic capacity, strength and coordination capacity,can be maintained or improved to a certain extent withthe aid of exercises, healthy lifestyle, prevention ofdisease and vocational training.9'23'33'50-53 The otherpotentials, such as eyesight and hearing, could beenhanced with simple measures at work such as betterillumination and minimizing unnecessary ambient noise.In comparison, mental potential is less amenable toenhancement.

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486 Occup. Med. Vol. 50, 2000

HEALTH AND WORK DISABILITY

The health status of the ageing worker is lower than thatof younger workers. There is a definite increase in theprevalence and incidence rate of diseases, including thatof occupational and work-related diseases.3 It is estimatedthat between one-third and two-thirds of workers aged 50years and older have at least one diagnosed disease,mainly musculoskeletal or cardiovascular.5 Most preva-lent are arthritis (53%), hypertension (42%), hearingimpairment (40%) and heart disease (40%).33 This maytranslate to an inherently higher health care cost. Theelderly also have a higher incidence of certain psychiatricconditions, such as depression and dementia.45

Work disability refers to the inability to work due toillness or disability.54 All the above factors contribute tothe higher work disability rates seen in ageing workers.54

Others include pyscho-social factors and healthy livinghabits of the individual.55

Where workers were grouped into physical, mental ormixed physical and mental job categories (to bediscussed in the next section), the highest diseaseprevalence is found in physically demanding occupationsand for men in work with mixed demands.31 Femaleauxiliary workers, domestic helpers and cooks, as well asmale installation and transport workers, exhibited thepoorest health. Men and women in intellectual workexhibited the best health and work ability.

In associated studies of mortality, disability andchanges in occupation among ageing workers in adeveloped country, the rates were highest in occupationsinvolving heavy physical work, poor work posture and apoor physical environment.56 This was especially so ininstallation and auxiliary male workers. The maindiseases which led to disability included malignancy,coronary artery disease, congestive heart failure, rheu-matoid arthritis, bronchitis and mental illness.56

Work stress can be a real problem in the ageing worker.9

Some studies have shown that stress levels are higher in theolder working populations. This has significant implica-tions on the health and well-beingof the worker as ithas beenobserved that work-stress related reactions were associatedwith both mortality and disability.3l In the model of ageingproposed by Goedhard,57 it was suggested that stress is anexternal source that might influence the rate of ageing.People with increased work stress show more adversechanges in body functions than others.62 The repercussionsextend beyond the individual: it involves other employees,the employer, as well as families and society at large.58

In assessing fitness to work for the ageing worker, it islikely that the worker may have some form of chronicillness. One may want to assess work disability for thatparticular illness and also correlate with his functionalstatus or work ability.38'54'55'59"61

UNDERSTANDING THE NATURE OF WORKAND ITS ENVIRONMENT

A medical assessment alone is not sufficient to assessemployability of a worker. The physician needs to

understand the environmental risks involved and thenature of the job. This becomes even more relevant whenworkplace adjustments may be recommended to suit theability of the ageing worker in meeting the needs of theemployer.3

Nature of work

Although there have been a number of methodsproposed to classify occupations, these have largely beenused in research to study the relationship between workand health. For practical purposes, for ageing workingpopulations, the nature of work could be convenientlyclassified into physical, mental or mixed (a combinationof physical and mental) .62>63 Physical work is dominatedby muscular work and high physical work load asexemplified by auxiliary work, installation and homecare. Mental work primarily demands mental effort, asseen in administrative and management jobs, technicalsupervision and teaching. The mixed work group ischaracterized by both physical and mental effort, such asnursing, transport, kitchen supervision and dental work.

Such a classification would assist in matching theageing worker's functional capacity with his jobrequirements. For instance, a high degree of physicalcapacity would be required for a 'physical' job scoperather than mental capacity. Conversely, one withphysical disability need not necessarily be excludedfrom an administrative job.

The U.S. Department of Labor in its Dictionary ofOccupational Titles has refined this concept effectively.Jobs are graded according to physical demands, environ-mental conditions, certain levels of skill and knowledge,and specific vocational training required. Parametersassessed for physical demands include strength (ex-pressed by sedentary, light, medium, heavy and veryheavy), climbing/balancing, stooping/kneeling/crouch-ing/crawling, reaching/handling/fingering/feeling, talking,hearing and seeing (expressed by acuity, depth percep-tion, field of vision, accommodation and colour vision).64

Work environment

The work environment plays a prominent role inevoking negative health outcomes in workers. Ageingworkers are at higher risk of work-related andoccupational diseases. This may be due to having alonger cumulative exposure to work hazards such aschemicals or noise.3 Furthermore, there is likely to bean associated impairment of organ function. This iscomplicated by a higher unpredictability of the ageingworker's response to exposure to various workhazards.65 The implication is that certain environ-mental conditions should warrant a pre-employmentand periodic fitness to work examination for theageing worker to protect his health.

The WHO Study Group on 'Ageing and WorkCapacity' has described several aspects of workingconditions which should derive special attention in thecase of ageing workers.3 These factors are summarized inTable 1, and include:

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G. Chan et a/.: Ageing and fitness to work 487

BOX 1. A suggested work checklist to be used when determining an ageing worker's medical fitness*

MEDICAL HISTORY

Personal biodataAgeGenderDistance from home

Occupational historyMedical assessment

Medical historyDrug history

Social historyPhysical environmentFinancial statusFamily/social support

Lifestyle health factorsSmokingAlcoholPhysical exercise

PHYSICAL EXAMINATION/INVESTIGATIONS

VisionVisual acuity with Snellen's chart (both uncorrected

and corrected)Visual fieldExclude cataract/other age related changesColour visionAdequate for working environment?

HearingEase of communication with patientWhispering question out of patient's viewOtoscopic examination for ear wax impactdon in

elderlyAudiogram if requiredAble to hear danger/warning signals

Aerobic capacityCardiorespiratory medical examinationStress ECG/exercise toleranceRespiratory function testsSubmaximal exercise testsAerobic capacity

Upper and lower limb function andmusculoskeletal capacityAny deformities

Any tremor or rigidityExclude any orthopaedic conditionsFunctional assessment e.g. grip strength,

coordination, ability to pull/pushRange of movementGaitMobility

BalancePostural sway with eyes closed and manually

pushingAny postural hypotensionVertigo/tinnitus present

Mental stateGeneral assessmentAbility to understand and perform workAbility to follow instructionsAbility to communicate and interactAbility to manage own safety at workGeneral health questionnaireMini-mental examination for cognition and

depression in elderlyPsychiatric referral when required

SPECIAL REQUIREMENTS (to list)

May include the provision ofspecial diets (e.g. low calorie, low salt);a designated clean area, which does not have to be

large, for self-treatment, such as injections;arrangements to cope with an inability to tolerate

shiftwork — if possible, fixed hours should bedefined;

frequent rest periods—the supervisor should beinformed;

uncluttered work stations that are modifiedreasonably to suit the worker, e.g. with betterillumination;

easy accessibility to the workplace—appropriatetransport arrangements should be made.

FITNESS TO WORK

Yes, with the following requirements (list)No, for the following reasons (list)

*For completeness this checklist should be combined with the information outlined in Box 2.

• work organization—pace of work, working hours,variety;

• psychological factors—work roles, participation, con-trol;

• ergonomic factors—repetitive jobs, posture, handlingof heavy materials, speed, precision, anthropometricchanges;

• physical factors—noise, vibration, heat, pressure,lighting;

• chemical factors—cumulative hazardous chemicalexposure.

These factors often translate to 'stress' factors. In astudy of 13 occupational groups in Finland, the datahave suggested that the older worker in the workenvironment is often exposed to more than 10 stressfactors at levels that exceed 50% of the maximaltheoretical duration, frequency or significance.3'53

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Table 1.worker*

Working conditions that are important for the ageing

Factor Comments

Work organizationPace of work

Working hours

Variety

Pace should be comfortable for worker ratherthan set by machines/organization

Shorter working hours especially if work isphysically or cognitively demanding

Breaks necessaryWorkers of limited physical and cognitive

abilities benefit from variety

Psychological factorsWork roles Roles to be definedJob security Will affect performance and health

Ergonomlc factorsRepetitive jobsPostureHandling of heavy

materialsSpeed

PrecisionHigh aerobic demandsAnthropometric

changes

Physical factorsNoise

VibrationHeatPressureLighting

Chemical factors

Susceptible to musculoskeletal disordersLower tolerance to awkward posturesLower muscle strength and degenerative joint

diseaseBody movements not as quick for certain

tasksRequires static loading and good lightingRisk of fatigue and accidentsChanges in physique

Hearing difficulties and easily disturbed inconcentration-demanding jobs

Lower tissue and muscle stress toleranceLower tolerance to extreme temperaturesLess tolerance to hyperbaric conditionsLower adaptation to poor lighting

'Information given in this table is based upon that in the WHO technical reportAgeing and Working Capacity.3

BOX 2. Assessing job demands

REQUIREMENTS OF THE JOB

Work demandsWork environment and safetyErgonomic aspectsTravel requirements (if any)

Physical/intellectual/perceptualList risk factors:Specify if any:

It is difficult to identify specific occupations fromwhich the ageing worker should be excluded. Chron-ological age by itself should not be an absolutecontraindication, and it should be based upon theoccupational health and safety legislation for theparticular occupation.

DETERMINANTS OF WORK ABILITY

Work ability is an interaction of social, environmentaland individual factors, including physical fitness, copingskills, social support behaviour and health behaviour.9'66

In other words, work ability does not depend onfunctional capacity alone. It is complicated by theinfluence of external factors such as task demands,subjective effects of workload, objective effects of work-load, and latitude of control.67 Furthermore, functionaldecrease could result in reduced job productivity and ahigher risk of occupational and work-related diseases,thereby initiating a vicious cycle of deteriorating func-tional capacity and work ability. Matching workers withjob demands, whether physical, mental or mixed, maytherefore ensure some degree of work-relatedness andpromote individual work performance.

Despite the number of studies undertaken, there isvery little information of how much these factorscontribute to an individual's work ability. Ageing wasconsistently found to reduce work ability. For instance, itwas shown that a significant decline occurs after a meanage of 51 years and the annual decline of work ability washighest for women at 51 years.10'62 In the same study, itwas found that at least 25% of installation, auxiliary ortransport workers had a poor work ability rating, as didwomen doing kitchen supervision and home care work ata mean age of 58 years. Other important factors includedmental symptoms and musculoskeletal disease. Poorwork ability was also particularly associated withoccupations that involved mixed physical and mentalwork, followed by physical work (blue collar workers).Men and women whose jobs involved mostly mentalwork reported the best work ability.62

Associations were also found between high physicaldemands at work, poor physical work environment, lackof freedom, decreased recognition and esteem, increasein standing at work, and a decrease in vigorous leisure-time physical exercise.23'68

Conversely, factors at work which seemed to promotework ability included improvement of the supervisor'sattitude, decreased repetitive movements, and physicalexercise during leisure time.23 In workers who hadexisting cardiovascular disease, a low level of muscularwork and a high level of leisure-time physical exerciseappeared to decrease work disability. When comparedwith work ability of active workers, work disability waslinked to individual rather than workload factors.10

It has also been found that ability of the ageingworkers has improved significantly over the years. In aCalifornian study which tried to justify a later retirementage, it was observed that men and women in their 60s,i.e. those in the older working ages and youngerretirement ages, reported a significant improvement intheir ability to work.48 The change in work ability wassignificant enough to show that the percentage unable towork at the age of 67 years in 1993 was lower than thepercentage unable to work at the age of 65 years in 1982.The improvement in health was attributed to the highereducational status, better health and a decline in theprevalence of cardiovascular disease and arthritis. It has

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G. Chan ef a/.: Ageing and fitness to work 489

also been shown that both older and younger workerswere able to improve their work ability.23

It is a challenge to try to integrate the different facetsof individual characteristics and functional capacity intoa specific work ability index for different occupations.Unfortunately, attempts to determine an objectivemethod of combining physiological, biochemical andpsychological data, which yields an index of thebiological age of the individual (a biological marker ofageing) has so far not been successful.69'70

On the other hand, subjective indices on work abilitydevised by various investigators have shown that it ispossible to measure work ability by means of asummarized index, but unfortunately, these have so farnot been validated. These indices have been based on avariety of factors including self-assessments of health andwork capacity, clinical evaluation, life-style factors,objective tests to measure aerobic capacity, workenvironment and demands, and work perfor-mance.9'10'23'62'66'68'71 ~75 A programme for ageingworkers at the workplace could include regular monitor-ing of a work ability index.7

Some of the findings have shown good correlationwith the clinical assessment of health status and workability at the group level.76 It was found that of thephysical capacity tests, muscular strength correlated bestwith work ability when compared with cardio-respiratorycapacity. Mental capacity tests, including visuo-motorspeed, also had consistently lower correlation thanphysical capacity tests.74 Others have also indicated thatsuch tests have predictive value in assessing a laterdisability to work.

The work ability index has other applications. It hasbeen used as a marker to predict an improvement ordecline in work ability in later life.9'75 It has also beendeveloped for use to identify early signs of decreasingwork ability, such that preventive measures could beplanned. There has been limited success for a fewoccupations including fire fighters, construction workersand teachers.77"79

PERIODIC ASSESSMENTS AND OTHERASPECTS OF FITNESS TO WORk IN AGEING

In periodic assessments, fitness for work does not usuallyend with a medical and work ability assessment. There isan important role for maintaining functional capacityespecially in the case of the ageing worker. Measures willinclude health promotion such as policies on smoking,diet, alcohol consumption and physical exercise.80

With a higher incidence of disease, appropriatescreening for chronic diseases becomes more relevantin the ageing worker. Disease screening should followthe guidelines of the respective major organizations andagencies such as the American College of Medicine,U.S. Preventive Service Task Force, American Acad-emy of Family Physicians or other professional organi-zations.81 The main difficulties, sometimes, are the lackof effective tests or screening tools. Diseases which canbe usefully screened include hypertension, diabetes

mellitus, hyperlipidaemia, and malignancies such ascervical cancer and breast cancer. It should be notedthat the U.S. Preventive Service Task Force and theAmerican College of Physicians find insufficient evi-dence for or against screening for those above 65 yearsof age, but do recommend screening those healthyindividuals between 65 and 75 years who have coronaryheart disease risk factors. Screening is not advised after75 years of age.

There may also be a wish to screen for psychologicalconditions of the ageing worker by assessing the socialwell-being and stress levels of the individual.82"85 Thiscould be done simply with the aid of a short generalhealth questionnaire and enquiring about the socialhistory.

It is also important to screen for disease factors whichmay have an impact on workplace safety. Ophthalmicdisorders such as cataracts and age-related macularchanges, aural problems such as conduction andsensori-neural hearing loss, and balance control such asinner ear disturbances, may be especially relevant in theelderly worker.

CONCLUSION

Work capacity or job performance in the ageing workeris multifactorial, involving an interaction between func-tional capacity, health and the nature of the work.Assessing fitness to work is thus a two-pronged processof identifying work ability (whether physical, mental ormixed) of the individual (while screening for pathologi-cal disease) and correlating it with the respective natureof the work, with reasonable job re-design. Besidesclinical or laboratory measurements, it is possible toconstruct a 'work ability index' for a specific occupationas a practical means of selecting the appropriate workerfor the job and monitoring his functional capacity. Thereis also a greater role for health promotion, diseasescreening for maintenance of functional capacity, andpossibilities for work accommodation.

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