Long working hours are inversely related to sick leave in the following 3 months: a 4-year registry study

Abstract

The aim of this study was to investigate the effects of long working hours (≥12 hour shifts) on sick leave using objective records of shift work exposure and of sick leave. Methods A total of 1,538 nurses (mean age: 42.5, SD: 12.0; response rate 42%) participated. Payroll and archival sick leave data over a four-year period were retrieved from employers' records and aggregated over every third calendar month. A multilevel negative binomial model was used to investigate the effects of exposure to long working hours, on subsequent sick leave rates the following three months. Covariates included prior sick leave, number of shifts worked, night and evening shifts, personality, and demographic characteristics. Results Exposure to long working hours was associated with fewer sick leave days in the subsequent three months [adjusted model, incidence rate ratio (IRR)=0.946, 95%CI=0.919-0.973, p<0.001]. The interaction long working hours by a number of work days showed that sick leave days the subsequent three months was higher by long shifts when number of shifts was high compared to when number of shifts was low [adjusted model, IRR=1.002, 95%CI=1.000-1.004, p<0.05]. Discussion Long working hours was associated with fewer sick leave days. The restorative effects of extra days off with long working hours are discussed as possible explanations to this relationship.

A case‐crossover study of age group differences in objective working‐hour characteristics and short sickness absence

“…This study had the strength of using objective working‐hour data without memory bias, attrition or selection based on exposure for almost 13 000 employees working in hospitals. Such data are existing in other cohorts (Dall'Ora et al, 2018; Vedaa, Pallesen, et al, 2019; Vedaa et al, 2017), but rare studies have focused on short (1–3 days) sickness absences as we have done in an earlier study based on partially the same data set but in which shift work was evaluated by work contract and data were from 2008 to 2015 (Ropponen et al, 2019). We had no loss to follow‐up and a specific strength was the possibility to objectively identify those who work shifts and night shifts.…”

“…Studies on shift work and sickness absence have yielded mixed findings. Some studies indicate increased risk of sickness absence due to long working hours (Dall'Ora et al, 2018), while some show negative associations (Bernstrom, 2018; Vedaa, Pallesen, et al, 2019). Our earlier studies, based on the Finnish Public Sector study, indicated that long working hours, several consecutive night shifts and short (<11 hr) recovery periods between the shifts are associated especially with short (1–3 days) sickness absence (Ropponen et al, 2019) but also with fatigue and sleep disturbances (Härmä, Karhula, Puttonen, et al, 2018; Härmä, Karhula, Ropponen, et al, 2018).…”

“…The earlier negative results on the association of shift work and sickness absence may also be due to lack of detailed information on working‐hour characteristics (Ropponen et al, 2019). In general, register‐based data on working hours have only recently become available to study the association of shift work with sickness absence (Dall'Ora et al, 2018; Ropponen et al, 2019; Vedaa, Pallesen, et al, 2019; Vedaa et al, 2017).…”

Patterns of working hour characteristics and risk of sickness absence among shift-working hospital employees: a data-mining cohort study

“…By implication, quick returns (ie, short recovery after shift) are inversely associated with long shifts, which may contribute to the unexpected findings in studies that are focused on a single working hour characteristic only because both quick returns ( 11 ) and long working hours ( 3 , 4 ) are associated with increased risk for negative health and well-being effects. An earlier study found that long work shifts were associated with less sick leaves among hospital employees working irregular shifts raising speculations that the risk estimates for long shifts were confounded by other protective effects, such as longer recovery periods after the long shifts ( 12 ). More generally, the researcher- or hypothesis-derived pre-defined shift work patterns represent only a small subset of possible patterns, whereas modern data-mining tools would allow systematic exploration through a vastly larger space of possible patterns present in the given data.…”

8. Bedre arbeid–familie-balanse med tolvtimersvakter i helsesektoren?

“…Mange ansatte trives med å jobbe turnus, og studier viser at de som arbeider langvakter og samarbeidsturnus, er blant dem som gir uttrykk for størst trivsel med å jobbe turnus (Moland & Bråthen, 2019). En studie viser også at langvakter reduserer risikoen for sykefravaer (Vedaa et al, 2018).…”