Patterns of drinking behaviour and incidence of diseases amongst Scottish adults Presented by: Dami Olajide

Background o Alcohol is linked to major diseases and a major risk factor for morbidity and mortality in the UK:  In Scotland, 2,882 (or 5% of total) deaths are attributable to alcohol & 1,492 deaths prevented in 2003 (Grant et al 2010).  Alcohol attributable deaths increased by 15% from , while hospital admissions increased by 7% (ScotPHO 2008). o Important heterogeneities exists in alcohol consumption;  Protective effects of alcohol;  The majority of diseases/conditions are partly attributable to alcohol;  Associated burden of diseases vary by demographics (e.g. age and gender) & other characteristics;  Individuals tend to under-report their drinking behaviour by up to 50% (ScotPHO 2008).

Aim and objectives o Aim is to shed some light on the nature of heterogeneities in alcohol consumption and disease burden amongst Scottish adults: (i)Exploit data linkage to identify the underlying patterns of consumption, based on individuals’ self-reported drinking status and hospital admissions; and (ii)Examine associated characteristics of the individual. o Major contribution is that (i) and (ii) are jointly undertaken in a single model.

Methods (1): Data o Linked data set:  Hospitalisation episodes from the Scottish Morbidity Records (SMR);  Respondent characteristics from the Scottish Health Survey (SHeS). o Incidence of an alcohol-related disease/condition:  Presence of specific ICD9 & ICD10 codes (N=4,984 or 24%)  Wholly or partially attributable to alcohol consumption (98% partially) o Disease categories:  abdominal/liver, cancers, heart (16%), nervous system/mental disorder, others-conditions; none.

Data (ctd.) o Alcohol consumption (units per week):  12 polytomous responses reclassified into 6: −Never drinker; Ex-drinker; Occasional or < 7 (42%); Over 7 – 14; Over 14-28; Over 28. o Respondent characteristics:  Age categories (16+), marital status, education, occupational social class, deprivation, health board (Greater Glasgow). − Average age = 46 years; female majority (55%), No education qualification (36%).

Methods (2): Approach o Latent class analysis (LCA) approach  statistical method used to identify homogenous, mutually exclusive groups (classes) existing within a heterogeneous population.  Widely used in health care research to analyse behavioural patterns. o Latent class regression model  A single model for LCA for polytomous responses + regression (Linzer and Lewis 2011)  Item-response probabilities are obtained from LCA based on self- reported drinking status and related diseases/conditions  Characteristics associated with class membership are then obtained from regression. o Separate analysis for females and males.

Results (1): Latent class profiles FemalesMales C 1C 2C 3C 3C 1C 2C 3C 3 Pr (class membership) Alc. consumption: Never drk Ex-drinker Occ. or < Over Over Over SMR post survey: None Abdominal/liver Cancers Heart Nervous/mental Other (conditions)

Profiles continued (notes only)

Results (2): Graphical displays Fig.1. Females Fig.2. Males

Characteristics of class membership FemalesMales Variables:(2/1) Age:No clear age effectClear age effect (increasing) Marital status:Lower for divwidsepLower for married or cohabiting Education qual:Decreasing progressivelySignificant only at degree level Occ. soc. class:Decreasing progressivelyNo association Deprivation:Increasing progressivelySignificant only for most deprived. Gtr. Glasgow:No associationPositive association (3/1) Age:Increasing progressivelySimilar Marital status:Married/cohabiting positiveSimilar Education qual:Decreasing progressivelySimilar, but lower in magnitude Occ. soc. class:Decreasing progressivelySimilar Deprivation:Increasing progressivelySimilar Gtr. Glasgow:No associationPositive association

Preliminary conclusions o Given their patterns of alcohol and related diseases/conditions:  Important gender differences at moderate level of risk (2/1) (age, education qualification, social class, health board). Women with better education and social class are at a lower risk of alcohol-related diseases/conditions than men of similar characteristic.  No clear gender differences in characteristics at highest level of risk (3/1). o Some indication of under-reporting: objective measures of alcohol consumption may reduce under-reporting. o Diseases are largely partially related to alcohol. o Further work: policy implications of findings