Is there a link between per capita alcohol consumption and youth drinking? A time–series analysis for Sweden in 1972–2012

AIMS: To estimate the relationship between per capita alcohol consumption and youth drinking in Sweden during the last 40 years and to estimate the relationship between female and male youth drinking during the 40‐year study period. DESIGN, SETTING, PARTICIPANTS AND MEASUREMENTS: Per capita alcohol consumption was proxied by official sales data, supplemented by data on unrecorded consumption. Youth consumption was measured by a question on heavy episodic drinking (HED) included in an annual school survey of alcohol and drug habits among Swedish 9th ‐grade students (15–16 years of age). The annual samples comprise approximately 5000 individuals (with roughly equal numbers of boys and girls) with response rates in the range 80–93%. The study spans the period 1972–2012. Autoregressive integrated moving average (ARIMA) time–series analysis was used to estimate the relation between per‐capita alcohol consumption and youth drinking. Ocular inspection of the time–series data suggested a stronger synchronization between the two series in the early period, before the mid‐1990s, than in the later period, indicating a structural shift in the relation at issue. We therefore conducted period specific time–series analyses with 1995 as the year of division. RESULTS: There was a statistically significant relation between per capita alcohol consumption and HED among youth for 1972–94. A 1% increase in per capita alcohol consumption was associated with an increase in HED of 1.52% (P = 0.008). The estimate for 1995–2012 (0.12) was well below statistical significance (P = 0.580). The estimated elasticity of the association between boys’ and girls’ HED during 1972–94 was close to unity (0.98, P < 0.001), suggesting proportional changes in boys’ and girls’ drinking. When controlling for per capita consumption, the association was halved (to 0.55) but still significant in table 3 (P = 0.045). CONCLUSIONS: Adult and youth drinking in Sweden were synchronized closely during the two last decades of the 20th century, but youth drinking developed an independent trajectory shortly before 2000.