No Link Between Drinking Alcohol and Increased Parkinson’s Risk in Women, Large UK Study Finds
Drinking alcohol does not increase the risk of developing Parkinson’s disease in women in the United Kingdom, nor are there increased risks linked to the consumption of different types of alcohol, a large study has concluded.
The study, “Alcohol intake and Parkinson’s disease risk in the million women study,” was published in the journal Movement Disorders.
Several studies have investigated the link between alcohol intake and the risk of Parkinson’s disease, albeit with contradictory results: While some reports suggest people who drink alcohol have a lower risk of developing Parkinson’s disease, other studies show no effect.
Some studies have suggested that different types of alcohol (beer, wine, and liquor) can influence Parkinson’s risk differently, with low beer consumption linked to a lower Parkinson’s risk and liquor associated with a higher Parkinson’s risk.
However, most of these studies have been retrospective — based on information collected about the past — which rely on people accurately remembering details about their lives, and many studies did not properly control for other influential lifestyle factors such as diet, exercise, and smoking (confounding factors), which can affect the conclusions.
Moreover, many of these associations between alcohol and Parkinson’s were found in men but not women.
Therefore, a team of researchers based at the University of Oxford in the United Kingdom conducted a prospective study — following individuals over time — of a large group of women in the U.K. to examine the association between Parkinson’s and alcohol intake.
Participants were recruited from The Million Women Study — a U.K. initiative that collected information on the lifestyle and medical histories of more than 1.3 million women, ages 50 to 64, to investigate how reproductive and lifestyle factors affect women’s long-term health.
At the beginning of the study, a total of 1,309,267 women without Parkinson’s completed a questionnaire on weekly alcohol consumption. They were asked to identify different alcohol types they consumed that each contained approximately 10 grams of pure alcohol (glass of wine, half-pint of beer/cider, or a shot of liquor) and reported a number of drinks per week ranging from no alcohol to 21 or more drinks.
After 14 years, 44,524 participants completed an additional 24-hour diet recall questionnaire to measure their alcohol intake.
Women who went on to develop Parkinson’s were identified through hospital or death records. After an average follow-up time of 17.6 years, a total of 11,009 women developed the disease.
Data analysis found that, compared with drinkers, non-drinkers with an alcohol intake between zero and one drink per week had an increased risk of developing Parkinson’s. However, because some women in the early stages of Parkinson’s can change their drinking habits, the team excluded data from the first 10 years and found the risk for non-drinkers was lower.
The higher Parkinson’s risk in non-drinkers may reflect that in the early stages of the disease, parts of the brain associated with alcohol drinking behavior may be damaged, making a person that goes on to develop Parkinson’s less likely to drink.
For women who consumed more than 14 drinks per week, the risk of developing Parkinson’s was the same as women who drank one to two drinks per week, in both the first 10 years and after more than 10 years of follow-up.
No increased risks were found between women who drank only one type of alcohol and those who drank more than one type.
The research team also found no association between alcohol consumption and Parkinson’s in those who never smoked cigarettes, and these results remained whether women had cardiovascular disease, drank coffee and tea, or had a family history of Parkinson’s.
“In this analysis of a large, prospective cohort of women in the UK, we found little evidence for an association between usual alcohol intake and [Parkinson’s] risk,” the authors reported. “Nor was there any evidence of an association between intake of specific types of beverages and [Parkinson’s] risk.
“The results suggest that alcohol intake does not materially influence the risk of [Parkinson’s] in UK women,” they concluded.