This article provides an overview of the design and methodology of the “Corona lockdown: how fit are you?” (CLOFIT) study, including the questionnaires and scales that were included in the online survey. The aim of the CLOFIT study was to investigate the psychosocial and health consequences of the coronavirus disease 2019 (COVID-19) pandemic in the Netherlands. The survey was conducted among the Dutch population to collect data on immune fitness and the psychological and health consequences of the 2019 coronavirus disease (COVID-19) pandemic lockdown in the Netherlands. The CLOFIT dataset contains measures from N = 1910 participants and is broadly representative of the Dutch general population. The dataset represents both sexes, a range of ages including the elderly, different education levels, and ethnic backgrounds. The cohort also includes people with a diverse health status and range of medication use.

The aim of this study was to explore the effects of the 2019 Coronavirus (COVID-19) lockdown on mood states, stress, alcohol consumption and perceived immune fitness in a Dutch sample. Analysis included a subsample from the “Corona Lockdown: how fit are you?” (CLOFIT) study, comprising N = 761 participants who reported consuming alcohol in 2020. Results show that, compared to pre-lockdown, the first COVID-19 lockdown (March 2020) was associated with experiencing poorer mood (e.g., anxiety, depression, loneliness, fatigue) and increased stress levels. Among younger participants (18 to 35 years old), a significant decrease in weekly alcohol consumption was found during COVID-19 lockdown, which was not significant in older individuals. For the younger age cohort (18 to 35 years old), increased stress significantly correlated to increased weekly alcohol consumption (r = 0.163, p = 0.003), which in turn, correlated significantly to reporting a poorer perceived immune fitness (r = −0.165, p = 0.002). Poorer perceived immune fitness correlated significantly with increases in the presence and severity of COVID-19 symptoms (r = −0.313, p < 0.001, and r = −0.325, p < 0.001, respectively). The data provides evidence for significant relationships between changes in mood, stress and alcohol consumption during COVID-19 lockdown, and supports a model that links these changes to perceived immune fitness and susceptibility to experiencing COVID-19 symptoms.

Since the outbreak of the 2019 coronavirus (COVID-19) pandemic, lockdown periods have been installed to counteract the spread of the virus. These lockdowns, characterized by social isolation, have been associated with mood changes and increased stress. Individuals have used various strategies to cope with the negative effects of being in lockdown, including increasing the frequency and quantity of alcohol consumption. The aim of this study was to investigate mood before and during lockdown of individuals who reported consuming more, less, or the same amount of alcohol during lockdown, and examine how this impacts and perceived immune fitness and the presence and severity of COVID-19 symptoms. Analysis included a sub-sample from the ‘Corona Lockdown: how fit are you?’ (CLOFIT) study, comprising N = 761 participants who reported consuming alcohol in 2020. The results of the online survey showed that half of the participants did not alter their weekly alcohol consumption during lockdown (50.4%), whereas 25.9% of drinkers reported a reduction and 23.8% reported an increase in weekly alcohol consumption. Compared to individuals that did not alter their drinking behaviour, both increased and reduced alcohol consumption during lockdown was associated with poorer mood and higher stress levels. Increased alcohol consumption was associated with significantly reduced perceived immune fitness and a high presence and severity of COVID-19 symptoms. This effect was not significant among individuals with reduced or unaltered alcohol consumption.

Aim To investigate the relationship between age and hangover frequency and severity. Method An online survey, generated through Facebook, collected self-report data relating to alcohol consumption from 761 Dutch alcohol consumers aged 18–94 years (61.6% female). Results Overall, young individuals consumed more alcohol than older drinkers, and men more than women. Significant interactions between age group and sex were found for both subjective intoxication and hangover severity, indicating that the sex differences in these variables were greatest in the younger age groups but became significantly smaller or absent in the older age groups. Partial correlations, correcting for estimated blood alcohol concentration (eBAC), revealed significant and negative partial correlations between age and subjective intoxication (r = −0.444, P &lt; 0.0001), age and hangover severity (r = −0.327, P &lt; 0.0001) and between age and hangover frequency (r = −0.195, P &lt; 0.0001), i.e. subjective intoxication, hangover severity and hangover frequency decline with age. With regard to sex differences, the observed correlations with age for the past month heaviest drinking occasion were stronger in men for subjective intoxication, (z = −2.25, P = 0.024), hangover severity (z = −3.36, P = 0.0008) and hangover frequency (z = −3.63, P = 0.0003). Conclusions Hangover severity declines with age, even after controlling for eBAC or the amount of alcohol consumed. Sex differences were greatest in the younger age groups but became significantly smaller or absent in the older age groups. The relationship between age and hangover severity is strongly mediated by subjective intoxication. Pain sensitivity, lower with aging, might be a mediator.

The purpose of this study was to compare alcohol consumption between the heaviest drinking occasion in the period before the coronavirus disease 2019 (COVID-19) lockdown (15 January–14 March 2020) and the first COVID-19 lockdown period (15 March–11 May 2020) in the Netherlands, including the presence and severity of associated hangovers. The analysis included a sub-sample from the “Corona Lockdown: how fit are you?” (CLOFIT) study, comprising N = 761 participants who reported consuming alcohol in 2020. Overall, on the heaviest drinking occasion during the first COVID-19 lockdown period a significant reduction in number of alcoholic drinks consumed on the heaviest drinking occasion, drinking duration, and estimated BAC was observed. A significant reduction was also observed for subjective intoxication and next-day hangover severity. During the lockdown period, a significant reduction in the frequency of alcohol hangovers was reported. Several age and sex differences were observed. Specifically, men consumed significantly more alcohol than women and experienced hangovers significantly more frequently, both before and during the lockdown. With regard to age, young adults (18–35 years old) significantly reduced their alcohol intake on the heaviest drinking occasion during the lockdown and also reported lower ratings of subjective intoxication and hangover severity. No significant changes were seen for individuals above 35 years old. In conclusion, the first COVID-19 lockdown in the Netherlands was associated with reduced alcohol intake on the heaviest drinking occasion and a reduction in the severity of hangovers, particularly among young male adults.