Table 1.
Description of baseline confounders of patients prescribed varenicline or nicotine replacement products
| Varenicline | Nicotine replacement products | |||
|---|---|---|---|---|
| N = 52981 | N = 122159 | |||
| (%) | SD | (%) | SD | |
| Male | 49.3 | 45.9 | ||
| Age (years)a | 44.3 | 13.1 | 46.1 | 15.6 |
| Prescribed in 2007 | 12.7 | 25.4 | ||
| Prescribed in 2008 | 19.4 | 17.7 | ||
| Prescribed in 2009 | 19.1 | 17.3 | ||
| Prescribed in 2010 | 20.1 | 14.7 | ||
| Prescribed in 2011 | 18.4 | 12.5 | ||
| Prescribed in 2012 | 10.3 | 7.1 | ||
| Number of GP visits in previous yeara | 6.3 | 8.9 | 12.0 | 11.2 |
| Diagnoses in the previous year | ||||
| Autism | 0.0 | 0.0 | ||
| Bipolar | 0.0 | 0.2 | ||
| Current smoker | 61.4 | 61.6 | ||
| Dementia | 0.0 | 0.1 | ||
| Depression | 3.8 | 6.5 | ||
| Eating disorder | 0.0 | 0.1 | ||
| Hyperkinetic disorder | 0.0 | 0.0 | ||
| Learning disability | 0.0 | 0.1 | ||
| Neurotic disorder | 2.0 | 3.4 | ||
| Other behavioural disorder | 0.0 | 0.0 | ||
| Personality disorder | 0.0 | 0.1 | ||
| Schizophrenia | 0.0 | 0.3 | ||
| Alcohol misuse | 0.9 | 1.7 | ||
| Probable self-harm | 0.0 | 0.0 | ||
| Drug misuse | 0.1 | 0.3 | ||
| Fractures | 1.3 | 1.8 | ||
| Any psychiatric illness | 6.0 | 10.5 | ||
| Chronic disease | 7.7 | 11.2 | ||
| Prescriptions in the previous year | ||||
| Antidepressant | 17.0 | 26.5 | ||
| Antipsychotic | 2.9 | 6.4 | ||
| CNS stimulant | 0.0 | 0.1 | ||
| Dementia medication | 0.0 | 0.0 | ||
| Hypnotic anxiolytic | 4.7 | 7.0 | ||
| Lithium | 0.1 | 0.4 | ||
This sample was larger than used Thomas and colleagues (2013) as in this study we also included patients who attended general practices that were not linked to the Hospital Episodes Statistics data.18
aContinuous variables, mean and standard deviation (SD) reported.