High-risk alcohol consumption (>180 g/week) was associated with poorer self-reported sleep quality as well as worse values in actigraphy-derived sleep parameters, including sleep efficiency, Wake After Sleep Onset, number of awakenings, and sleep fragmentation index.
Key Findings
Results
High-risk alcohol consumption was associated with higher Pittsburgh Sleep Quality Index (PSQI) scores, indicating poorer self-reported sleep quality.
Participants consuming more than 180 g/week of alcohol were classified as high-risk consumers.
An association was found between alcohol consumption measured in grams/week and PSQI score.
The study used the Pittsburgh Sleep Quality Index (PSQI) as a self-reported measure of sleep quality.
The sample consisted of 500 individuals aged 25–65 selected via stratified random sampling by age and sex from a health card database in Salamanca and Ávila, central-western Spain.
Results
High-risk alcohol consumers had more awakenings and a higher sleep fragmentation index compared to non-drinkers.
Participants in the high-risk group (>180 g/week) showed more awakenings than those reporting no alcohol consumption.
The sleep fragmentation index was also higher in the high-risk consumption group compared to non-consumers.
These parameters were measured objectively using actigraphy.
The cross-sectional design precludes causal inference.
Results
Significant differences in sleep efficiency and Wake After Sleep Onset (WASO) were found across all alcohol consumption categories.
Differences in sleep efficiency were statistically significant between all alcohol consumption categories, not only the high-risk group.
Wake After Sleep Onset (WASO) also differed significantly across all consumption categories.
Both sleep efficiency and WASO were measured objectively via actigraphy.
This suggests a dose-related pattern of alcohol's effect on these specific sleep parameters across the full range of consumption levels.
Methods
The study employed both objective actigraphy and subjective self-report (PSQI) to assess sleep quality in a community-based adult population.
A cross-sectional descriptive study design was used.
The sample of 500 individuals aged 25–65 was drawn via stratified random sampling by age and sex from the regional health service's health card database in Salamanca and Ávila, Spain.
Actigraphy provided objective measures including sleep efficiency, WASO, number of awakenings, and sleep fragmentation index.
The Pittsburgh Sleep Quality Index (PSQI) provided subjective sleep quality assessment.
Alcohol consumption was measured in grams per week and categorized into consumption groups including a high-risk category of >180 g/week.
Background
Alcohol is described as one of the most widely consumed psychoactive substances worldwide, with frequent and excessive consumption linked to impaired sleep quality.
The study situates alcohol-related sleep impairment within a broader public health context.
The study population was community-based adults aged 25–65 years, not clinical or treatment-seeking populations.
The research was conducted in central-western Spain, providing data from a community sample in a European context.
What This Means
This research suggests that drinking alcohol at high levels — more than 180 grams per week, which is roughly equivalent to about 15 or more standard drinks — is linked to worse sleep in multiple measurable ways. Adults who drank at this level reported poorer overall sleep quality on a standard questionnaire, and when their sleep was tracked with wrist-worn devices (actigraphy), they showed more nighttime awakenings, more fragmented sleep, lower sleep efficiency, and spent more time awake after initially falling asleep, compared to people who reported no alcohol use. The study involved 500 adults aged 25 to 65 living in two Spanish cities, selected randomly from the regional health service database to represent the general community.
Importantly, the study also found that differences in sleep efficiency and the amount of time spent awake after first falling asleep were significant across all levels of alcohol consumption — not just among heavy drinkers. This suggests that even lower levels of alcohol use may be associated with measurable changes in sleep architecture when tracked objectively, though the high-risk group showed the most pronounced effects.
This research matters because it used both a self-report questionnaire and objective wrist sensor data to capture sleep quality, adding confidence to the findings. Because the study was cross-sectional (a single snapshot in time), it cannot prove that alcohol causes poor sleep, only that the two are associated. Still, the results add to a growing body of evidence suggesting that alcohol consumption, particularly at high levels, may disrupt normal sleep patterns in everyday adults living in the community, rather than only in clinical populations.
Check Your Own Numbers
Upload your bloodwork. We'll cross-reference your results against this study and 4,700 others.
Gonzalez-Sanchez J, Jimenez-Vaquero C, Alonso-Dominguez R, Garcia-Yu I, Sanchez-Aguadero N, Crespo-Sedano A, et al.. (2026). Relationship Between Alcohol Consumption and Sleep Quality in a Community-Based Adult Sample From Central-Western Spain.. Drug and alcohol review. https://doi.org/10.1111/dar.70269