Incidence of Hospitalizations Involving Alcohol Withdrawal Syndrome in a Primary Care Population

Abstract

Importance: Alcohol withdrawal syndrome (AWS) is an important cause and complication of hospitalizations. Although common and preventable, the incidence of AWS during hospitalizations is poorly described.

Objective: To evaluate the incidence and proportional incidence of hospitalizations involving AWS in an adult primary care population overall and across patient characteristics.

Design, setting, and participants: This retrospective cohort study used electronic health records and insurance claims from Kaiser Permanente Washington (KPWA) between July 1, 2018, and June 30, 2022. The study included adults with 1 or more primary care visits during this period or the year prior, where primary care included annual standardized alcohol screening using the Alcohol Use Disorders Identification Test-Consumption (AUDIT-C).

Exposures: Age, sex, race, Hispanic ethnicity, AUDIT-C scores, and comorbid diagnoses.

Main outcome and measures: Hospitalizations involving AWS were defined by diagnosis codes documented during hospitalizations (incidence numerator). Time enrolled in KPWA determined person-enrolled-years (incidence denominator). Proportional incidence was calculated as the incidence of hospitalizations involving AWS divided by the incidence of all-cause hospitalizations. Proportional incidence was also estimated for hospitalizations involving other common chronic conditions (chronic obstructive pulmonary disease, diabetes, heart failure, and hypertension), which were also defined using hospital diagnosis codes.

Results: Among 544 825 adults engaged in primary care (mean [SD] age, 47.0 [17.9] years; 310 069 [56.9%] female; 3656 [0.7%] American Indian or Alaska Native, 55 206 [10.1%] Asian, 25 406 [4.7%] Black, 5204 [1.0%] Native Hawaiian or Other Pacific Islander, 365 780 [67.1%] White, 19 791 [3.6%] multiracial, 15 963 [2.9%] other races, and 53 819 [9.9%] unknown race; 33 987 [6.2%] Hispanic, 414 269 [76.0%] not Hispanic, and 96 569 [17.7%] unknown ethnicity), incidence of hospitalizations involving AWS was 169 (95% CI, 159-179) per 100 000 person-enrolled-years overall but as high as 15 347 (95% CI, 13 502-17 331) in patients with other alcohol-attributable diagnoses. The proportional incidence of hospitalizations involving AWS was 2.3% overall, with variation by age, sex, and AUDIT-C scores (eg, 9%-11% in male patients aged 30-49 years and 23%-44% in patients with high-risk AUDIT-C scores of 7-12 points). In most cases, among adults younger than 60 years, proportional incidence of hospitalizations involving AWS matched or surpassed that of other common chronic conditions (chronic obstructive pulmonary disease, diabetes, heart failure, and hypertension).

Conclusions and relevance: In this cohort study of a large primary care population served by an integrated health system, AWS hospitalizations were common, especially in male patients, younger age groups, and individuals with high-risk alcohol use. During hospitalizations, the burden of AWS was similar to or exceeded complications of other chronic diseases that receive greater medical attention.

Figure 1.. Variation in the Proportional Incidence of Hospitalizations Involving Alcohol Withdrawal Syndrome (AWS) Across Age Groups by Sex and Race

Proportional incidence is relative to all-cause hospitalizations. Alcohol withdrawal syndrome is defined by primary or secondary hospital diagnosis codes. Error bars indicate 95% CIs. Precise estimates and CIs are given in eTables 3 and 4 in Supplement 1.

Figure 2.. Proportional Incidence of Hospitalizations Involving Alcohol Withdrawal Syndrome (AWS) Across Age Groups by Alcohol Use Disorders Identification Test–Consumption (AUDIT-C) Screening Scores

Proportional incidence is relative to all-cause hospitalizations. Alcohol withdrawal syndrome is defined by primary or secondary hospital diagnosis codes. Error bars indicate 95% CIs. Precise estimates and CIs are given in eTable 5 in Supplement 1.

Figure 3.. Proportional Incidence of Hospitalizations Due to Alcohol Withdrawal Syndrome (AWS), Chronic Obstructive Pulmonary Disease (COPD), Diabetes, Heart Failure, and Hypertension Across Age Groups

Proportional incidence is relative to all-cause hospitalizations. Each outcome is defined using primary diagnosis codes only (consistent with the conventional approach used for measuring ambulatory care sensitive conditions). Error bars indicate 95% CIs. Precise estimates and CIs are given in eTable 6 in Supplement 1.