Lifestyle factors and changes in self-rated health during the COVID-19 pandemic: a Norwegian cohort study

Background Self-rated health (SRH) is an indicator for individuals’ overall perception of their physical, mental, and functional health. The COVID-19 pandemic and the associated public health measures disrupted lifestyle behaviours known to influence SRH, including smoking, alcohol use, diet and physical activity. Evidence on longitudinal SRH assessments during the pandemic and the modifying effects of lifestyle factors remains limited. This study aimed to examine longitudinal changes in SRH, associations with lifestyle factors at baseline, and whether these factors at the start of the pandemic were associated with differences in SRH trajectories. Methods This population-based longitudinal study collected data at three time points: April 2020 (T0), January 2021 (T1), and May 2022 (T2). SRH was assessed using a five-point item ranging from very good to very bad. Lifestyle exposures included smoking status, alcohol use, fruit, berry and vegetable intake, sugary food and beverage intake, and physical activity. Longitudinal associations were estimated using cumulative logit mixed effects models with individual-level random intercepts, adjusted for age and sex and presented with adjusted odds ratios (aOR) with 95% confidence intervals (CI). Results A total of 43,899 observations from 24,066 individuals were included. SRH declined significantly across the study period, with an aOR per time point of 0.79 (CI 0.77-0.82). High level of physical activity was associated with higher odds of better SRH compared to low activity (aOR 4.63, CI 4.13-5.19). High intake of sugary beverages and current smoking were both associated with worse SRH at T0, with aOR 0.46 (CI 0.37-0.57) and 0.46 (CI 0.40-0.52), respectively. Severe-risk alcohol use was associated with a faster decline in SRH over time compared to low-risk drinkers (aOR 0.76, CI 0.64-0.91). Conclusions Self-rated health declined significantly in this Norwegian population cohort over the two-year period during the COVID-19 pandemic. High level of physical activity was associated with substantially higher odds of better SRH at baseline, while severe-risk alcohol use was associated with a faster decline in SRH over the study period. Promoting healthy lifestyles including targeted measures toward severe-risk alcohol consumption, should be priorities in future public health emergencies.