Transcript Document
The following lecture has been approved for University Undergraduate Students This lecture may contain information, ideas, concepts and discursive anecdotes that may be thought provoking and challenging It is not intended for the content or delivery to cause offence Any issues raised in the lecture may require the viewer to engage in further thought, insight, reflection or critical evaluation Shiftworking Working Hours Shiftwork Human Behaviour Biopsychosocial model Mental Distress Dr. Craig Jackson Senior Lecturer in Health Psychology BCU “Peoples’ health should be no worse at the end of a working day than it was at the start” M.J. Harrington (1997) “People who work sitting down get paid more than people who work standing up” Ogden Nash (1902 - 1971) Core Occupational Diseases (EU) Chemical Inorganic Chemical Organic Biological Physical Dusts Physical Others Cadmium CS5 Zoonoses Asbestos Radiation Chromium Benzene Hepatitis Silica(te) NIHL Mercury Chlorine TB Mesothelioma Cataract Manganese Aromatics Vibration Nickel P.aromatics Dermatitis Lead Isocyanates 21st Century Workplaces • Global companies and operations • Leaner & Meaner managers • Gender issues • Disability issues • Migrant issues • Longer & less fixed working hours • Shorter contracts • Dirty jobs out-sourced Regulation of working hours 1800 – 1900 12 hour days & 6 day weeks Thomas Paine 1737 - 1809 Age of Reason Rights of Man Annie Besant 1847 – 1933 Reformist movement Fabian Society Secular Society “Fruits of philosophy” “The Link” “White slavery in London” 1889 Humanitarian concerns influenced change 48 hour week + regular rest = increased productivity Regulation of working hours 1900 – 1970 progressive reduction in working hours traditional work patterns 1970 working hours increase shiftwork increases irregular hours increase 24 hour processing technology unpaid extended hours flexible working annualised hours Regulation of working hours Linear Assumption of workers and productivity units reality units assumption time time Pieter Bruegel 1563 Wembley Stadium 326.5 Million pounds – Multiplex 2002 730 Million pounds British Library 32 Million pounds – estimate 511 Million pounds – 10 yrs late Scottish Assembly 37 Million pounds – estimate 431 Million Pounds – 3 yrs late PaddyPower .com Fatigue Stress Pilot Fatigue “Nodding off” Uncontrolled spontaneous episodes of sleep Can last seconds or minutes Disengages from reality and becomes unresponsive Fail to respond to outside information Aircraft cruising at 450 knots on glide path can travel nearly 730 feet during a one-second lapse. 123 feet Near Misses and Hits Regulation of working hours Environmental effects upon Performance Disturbed concentration Impaired memory Impaired decision making Mood changes Sleep disturbance Increased risk taking Paying Attention! Coping with Extreme Hours European directive on working time Organisation of work Min. daily rest period of 11 consecutive hours per 24 hours 1 rest break where working day > 6 hours Min. uninterrupted rest period of 35 hours per 7 day period Max. of 48 work per week Min. 4 weeks paid annual leave European directive on working time Night work Mean 8 hours work in any 24 hour period Free health assessment before assignment and at regular intervals Transfer to day work when suffering health problems connected with night work Night work and shifts Protection appropriate to the nature of the night work Prevention and protection services on parity with day workers Take account of principles adapting work to the workers Derogations Certain jobs junior docs Certain industries press media utility provision Circumstances where rests are not practicable Does not apply to: health checks provision of health and safety facilities Nearly 900 extra consultants will be needed by 2010 compensate for a reduction in doctors’ hours due to EWTD BMJ 2002;325:855 Shiftwork Any work regularly undertaken outside “normal” working hours Normal working hours = 07:00 – 18:00 Nights Early am Evening Fixed Rotating Eight hour Twelve hour Effects Circadian disruption Sleep loss Fatigue Social disruption Circadian Rhythms Body Temp Pulse Urinary excretion Blood pressure Hormonal changes Mental Performance Physical Performance Physiologically determined Socially modified & Externally cued Circadian Rhythms Adjustment to shiftworking Aprrox. 7 days to adjust to shift External cues hamper adjustment Nightworking sometimes never achieves adjustment Slow rotating shifts partial adjustment continual adjustment continual disrhythmia state Rapid rotating shifts no adjustment Adjustment to shiftworking stress strain Phase-shifting of waking and sleeping hours Impaired performance Impaired health Disturbed relationships modifying factors organisational effects > Absenteeism > Accidents > Labour turnover < Productivity Individual characteristics Job-related factors Environment Domestic Colquhoun & Rutenfranz 1980 Cardiovascular problems associated with shiftwork Increased Ischemic Heart Disease (IHD) Knutsson et al. 1986, 1988 Increased risk of IHD and Myocardial Infarction (MI) Akerstedt et al. 1986 Increased risk of Coronary V related disorders – Permanent Nightworkers Teiger 1984 Some studies show NO increased risk Bursey 1990 Chan et al. 1987, 1993 Kobayashi et al. 1992 Cardiovascular problems of shiftwork Liu & Tanaka 2002 – Japanese working men study 260 cases 445 controls Working Hours, Sleeping Hours and Acute MI Working hours related to: increased risk in year prior to AMI increased risk in month prior to AMI x2 increase in risk for overtime (>61 hours) x2-3 increase in risk for <5 hours sleep x2-3 increase for lack of sleep (2 or more days with <5 hours sleep) lack of sleep & few days off in recent past show > odds than those in past Overtime work and lack of sleep may be related to AMI Gastrointestinal disorders and shiftwork Indigestion (Chan et al. 1987) (Poole et al. 1992) Reflux Peptic Ulceration (Waterhouse et al. 1992) Related to: irregular hours circadian dysrhythmia poor catering facilities inequality in GP access Gastrointestinal disorders and shiftwork Irritable Bowel Syndrome (IBS) 13-52% new referrals to GI (Walker et al. 1990) Some occupations have > G.I than others (Cucino & Sonnenburg, 2001) IBD < in manual workers and farmers IBD > in sedentary workers Assoc. with occupation difficult to prove • shift workers seen as greatest risk of IBS • especially nightworkers • night workers present in GI more than day workers Access / Availability reasons ? Research fails to answer: genuine aspects ? psychosocial aspects of workers ? effects of shiftwork lifestyle ? Mental health problems and shiftwork Increased stress Alcohol consumption Neuroticism Review by Cole et al. 1990 OM Sources of performance impairment Day sleepers Endogenous factors Cortisol > Temp. > Exogenous factors Daylight Noise Societal bias Endogenous factors Melatonin > Temp. < Exogenous factors Darkness Societal bias Night wakers Current evidence Performance impairments more likely: on nightshift vs. morning or evening on advancing shifts vs. delaying shifts on rapid rotating shifts vs. slower rotation on irregular shifts regular shifts vs. at changeover periods in older shiftworkers where work is stressful Inconsistencies: 12 hour shifts Sex Performance effects – methodological considerations Task monotony cognitive skills Measures speed accuracy efficiency Individual aspects motivation perceived importance age ability health activity Situation / context supervision morale distractions 12 hour shifts Williamson et al. 1994 Australia 8hr vs. 12hr rotating computer operators psych health improved reduced tiredness Duchon et al. 1994 Canada 8hr vs. 12hr rotating miners improved sleep improved performance Chan & Gan Singapore 8hr vs. 12hr rotating electronic workers no health differences some headaches Groups prone to negative effects Over 50’s Morning types Long sleepers Personality types Heavy domestic commitments Multiple jobs Some physical conditions Psychiatric problems Employee Selection Issues ? Pre-employment counselling ? Standard Shiftwork Index (SSI) Barton et al. 1995 Questionnaires Work Context + Shift System Health Well-being Individual Differences Normative Data Training & Education Survey current work schedule Analyse data health effects performance safety quality of life Identify problem area(s) Recommend schedule changes Shiftworker education Asses & review information & awareness coping methods education lifestyle changes info Intervention strategies Organisation Slow / fast rotation (task considerations) Start times Rest breaks Expert systems Environmental Modification Bright lights Mood lights Temp. compensation Workload Facilities Evaluate process Evaluate outcome Health Surveillance Do what? How often? Individual Adjustment Pharmacological help Behavioural sleep management, diet, exercise, counselling Overtime working Extension of normal workday Extension beyond 8 hours (08:00 / 09:00 - 16:00 / 17:00) Non-paid is still overtime Increasing in UK especially managerial & professional groups 1990 UK had twice as many more employees on >48 hrs than any other EU countries More common in males Percentage of employees working less than 16 and more than 48 hours a week Overtime working (Europe 1990) Percentage of European employees working <16 hrs per week, and > 48 hrs per week, 1990 20 <16 >48 % 10 0 B DK F If graph was males only? G GR NL IRL I LU P E UK AV 0 ILO Rep. Czech Czech Republic Turkey Turkey S. Korea South Korea Iceland Iceland Swiss Switzerland Mexico Mexico Hungary Hungary USE United States Canada Canada Japan Japan Ireland Ireland UK Britain Australia Australia Portugal Portugal Greece Greece Italy Italy Spain Spain Denmark Denmark France France Germany Germany Norway Norway Sweden Sweden Austria Austria Belgium Belgium Finland Finland Netherlands Netherlands Employees working more than 40 hours a week - % of labour force, 1996 Employers >40hrs per week as % of labour force, 1996 100 Male Female 80 60 40 20 Source: ILO Potential effects cardiovascular mental health Stress immune system gastrointestinal musculoskeletal social effects Fatigue Exposure performance impairment safety problems over-exposure Cardiovascular disorders and overtime Increased Risk > 60hrs > 48hrs Night school students 50 – 60 hrs Overtime (females only) No increased Risk >10 hrs overtime / week “Overtime” BP & Serum Chol. Karoshi Range of CVIs 65%> if 60hrs / wk 1980 Mental Health 1985 SITES WITH MASS PSYCHOGENIC ILLNESS (USA) KIBBUTZIM (ISRAEL) ? No. of symptoms >8 hrs/ day < 50 Smoking Burnout X Psychiatric Status (Crown Crisp) Stimulant use/ Sleep disturbance Exhaustion/ Insomnia 1987 MUSIC THERAPISTS (USA) 1990 BUS DRIVERS (UK) ? 1991 COACH DRIVERS (AUSTRALIA) 30-70 1992 FEMALE HOSPITAL STAFF (USA) 32-19 1994 FACTORY WORKERS (JAPAN) ? Psychiatric State (GHQ) 1995 ACCOUNTANT (UK) ? Psychiatric Status (GHQ) 1991 1995 MANAGERIAL STAFF (USA/JAPAN) ? 50 55 Stress (OSI) 1991 1995 CLERICAL STAFF (USA/JAPAN) ACADEMICS ? Stress (OSI) 50 Stress (SACL) X 1996 Health & Well-being: Methodological Issues Mostly Cross-sectional studies Direction of any association ? Lag Healthy worker / Survivor Effects Response Rates Control Groups Exposure Assessment Outcome Measures Performance Effects: Accidents General Data Analyses suggests: Rise in accident rates after 9hrs work Cognitive (simulation) studies suggests errors increase after 8 hrs work HOWEVER Shift change from 8 to 12 hrs Safety record stays same Attitudes ? Safety culture increased ? Schedule org ? Nature of work ? Existing Gaps in Research Irregular Hours Increased concomitant exposure to other hazards Reproductive effects Family / Social influences Behavioural Effects Effect Modifiers Intervention procedures Further Reading Cooper, C.L., and Sutherland, V.J: Job Stress, Mental Health and Accidents among Offshore Workers in Oil and Gas extraction Industries. Journal of Occupational Medicine (1987) 29. Gann, M., Corpe, U., and Wilson, I. (1990) The Application of a Short Anxiety and Depression Questionnaire to Oil Industry Staff. Journal of the Society of Occupational Medicine 40: Glazner, L.K. Shift Work and its effects on fire fighters and nurses. Occupational Health & Safety, July 1992 Hanecke, K., Tiedemann, S., Nachreiner, F., and Grzech-Sukalo, H: Accident risk as a function of hour at work and time of day as determined from accident data and exposure models for the German working population. Scandinavian Journal of Work, Environment and Health (1998) 24(3). Further Reading Harrington, J.M., Shiftwork and health: a critical review of the literature. London, The Stationary Office, 1978. Harrington, JM. (2001) Health effects of shift work and extended hours of work. Occup Environ Med 58: 68-72. Jackson,C.A. (2002) Working hours and shifts in the petrochemical and gas industries: a review. Croner’s Occupational Hygiene 34: 13-17. Jackson,C.A., Spurgeon,A. and DeJong.G Mental Health of expatriate oil workers on extended twelve hour shifts in a desert-based oil field. Society of Petroleum Engineers. SPE 61016. Lees, R., and Laundry, B.R. Comparison of reported workplace morbidity in 8hour and 12-hour shifts in one plant. Journal of the Society of Occupational Medicine (1989) 39. Further Reading Lodden, T., The Effect on the Health and Safety of Older Offshore Personnel Long Shifts and Working Night Shift. Society of Petroleum Engineers. SPE 60996. Parkes, K.R.: Sleep patterns, Shift work, and Individual Differences: A Comparison of Onshore and Offshore Control-Room Operators. Ergonomics (1994) 37(5). Rosa, R.R: Performance, alertness, and sleep after 3.5 years of 12 hour shifts: a follow-up study. Work and Stress (1991) 5(2). Spurgeon A, Harrington JM, Cooper CL. (1997) Health and safety problems associated with long working hours: a review of the current position. Occup Environ Med; 54:367-375.