Depression is one of the common mental disorder in the world

Depression is one of the common mental disorder in the world. According to World Health Organization, depression is defined as the loss of interest in regular activity, low mood, change in appetite and sleeping pattern, poor concentration, fatigue, and sense of self-worthlessness. In 2016, about 6.7% of United States population i.e. around 16 million population suffer from at least one major depressive episode (National Institute of Mental Health). Depression generally begins at adulthood but in later life, it coexists with other health conditions like heart disease, cancer, diabetes etc. (National Institute of Mental Health). Risk factors of depression include family history of depression, major life changes, stressful situation and different health conditions (National Institute of Mental Health).
Drinking alcohol is one health behavior that is prevalent in every society. Excessive drinking is associated with increased morbidity and mortality. People who drink excessive amount of alcohol is in risk of disease conditions like liver disease, cardiovascular disease, mental disorders like depression, gastrointestinal disease etc. (National Institute on Alcohol Abuse and Alcoholism, 2016). Furthermore, older adults are more susceptible to alcohol related health conditions due to their physiological conditions, drug-alcohol interaction and other disease conditions (NIAAA, John, Montgomery & Tyas, 2008). About 3.3 million people around the world die due to excessive alcohol consumption which accounts more than death due to HIV/AIDS and Tuberculosis being a fifth leading cause of premature deaths and disability in the world in 2010 (World Health Organization, 2014).
John, Montgomery & Tyas (2008) conducted a cross-sectional study in Canada with older community adults aged 65 years and more. The data used in the study was from the representative sample of Manitoba on 1996-1997. In the study, CAGE (Cut down; Annoyed; Guilty; Eye-opener) scale was used to assess drinking behavior of older adults and score 1 and more than 1 was placed in the alcohol misuse category. People who never drink alcohol was placed in “never users” category, people who scored 0 in CAGE scale in “alcohol users” category and people who scored 1 and more than 1 in CAGE scale in “alcohol misusers” category. Older male adults were most likely to be alcohol misusers than females. It was found that there is no association of alcohol use and depression in this study. However, depression was associated with alcohol misuse and gender was found as a confounding variable as women were less involved in alcoholism, but depression was common among them than males (John, Montgomery & Tyas, 2008).
In the study conducted by Liu et. al. (2017) to find the relationship between alcohol and other factors associated with depression in China using the sample for China Health and Retirement Longitudinal Study on 2011 involving 7601 older adults aged 60 years and more, it was found that older male adults are more likely to be involved in drinking than female. However, it was found that males are less likely to have depressive symptoms than females. In addition, older adults living in rural areas are more likely to drink and have more incidence of depression than older adults in urban area.
Lee et. al. (2018) conducted four-year longitudinal study to understand the mutual relationship between drinking and depression among 2511 males between age 20 years and 65years. Forty one percent of the sample was adults aged 50 and more. Based on Korean Version of Alcohol Use Disorder Identification Test (AUDIT-K), 2191 were categorized as control group (AUDIT4 drinks per day or more than 10 drinks per week were categorized as heavy drinkers. In addition to this, participants were screened for Alcohol Use Disorder using CAGE questionnaire and categorized as nondrinkers (