Anxiety and depression in an older research population and their impact on clinical outcomes in a randomised controlled trial

INTRODUCTION

Anxiety and depression are common in older people living in the community. The aim of the study was to investigate their impact on clinical outcomes during a randomised controlled trial investigating the cost benefits of influenza vaccination in fit and healthy, independent living 65-74 year olds.

SUBJECTS AND METHODS

A total of 729 people were recruited. Participants completed the hospital anxiety and depression scale (HADS) and EuroQol EQ-5D quality of life questionnaire immediately before receiving vaccination and every two months for the next six months after this. Side effects three days after vaccination and Barthel score at baseline were also recorded.

RESULTS

At baseline the prevalence of "definite" anxiety in this sample (HADS score > or =11) was 4% and 1.2% of individuals had definite depression (HADS score > or =11). Individuals with anxiety or depression (HADS score > or =8) were more likely to complain of systemic side effects after vaccination and have a lower Barthel index score (p<0.001). Quality of life as measured by the EQ-5D visual analogue scale was reduced (p<0.001) at all time periods in those individuals with both anxiety and depression (HADS score > or =8 on both scales).

CONCLUSION

Although the prevalence of anxiety and depression in this sample was low, people with anxiety or depression were more likely to suffer from perceived side effects after influenza vaccine and have a lower Barthel and EQ-5D visual analogue score. In future studies the effect of anxiety and depression on older participants should be remembered and care taken to ensure that they do not affect results more than the intervention under study.

Side effects of influenza vaccination in healthy older people: a randomised single-blind placebo-controlled trial

OBJECTIVES

To investigate the frequency of side effects following influenza vaccination in healthy participants aged 65-74 years.

MATERIALS AND METHODS

A single-blind randomised placebo-controlled trial was performed in general practices in central Liverpool on 729 healthy individuals (341 females and 388 males) aged 65-74 (median age 68.9) years, of whom 552 received influenza vaccine and 177 received placebo. The main outcome measures were analysed from adverse reactions reported by the subjects on a postal questionnaire 3 days after vaccination.

RESULTS

724 (99.3%) questionnaires were returned. 62 (11.3%) participants who received influenza vaccination complained of local symptoms compared with 9 (5.1%) participants who received placebo (difference 6.2%; 95% CI 1.3 to 10.0%; p = 0.02). 192 (35.1%) individuals who received influenza vaccine complained of one or more systemic side effects compared with 75 (42.4%) who received placebo (difference -7.3%; 95% CI -15.6 to 0.9%; p = 0.10).

CONCLUSION

Healthy people belonging to this age group can be reassured that, when compared with placebo, influenza vaccination causes few, if any, systemic side effects and only a low incidence of local side effects.