Table 2.
Summary statistics for the key exposure and outcome variables over the 2006–2016 Health and Retirement Study waves (n=9,518)
| 2006 | 2008 | 2010 | 2012 | 2014 | 2016 | |
|---|---|---|---|---|---|---|
| Insomnia symptoms: | ||||||
| N | 9,518 | 7,509 | 5,803 | |||
| % Yes | 40.3 | -- | 41.4 | -- | 41.8 | -- |
| Mean ± SEM | 2.4 ± 0.02 | -- | 2.6 ± 0.02 | 2.7 ± 0.03 | ||
| 2006–2010: | ||||||
| % No change | 25.8 | |||||
| % Increase | 41.1 | |||||
| % Decrease | 33.0 | |||||
| 2010–2014: | ||||||
| % No change | 28.2 | |||||
| % Increase | 37.8 | |||||
| %Decrease | 34.0 | |||||
| 2006–2014: | ||||||
| % No change | 28.2 | |||||
| % Increase | 37.8 | |||||
| %Decrease | 34.0 | |||||
| Severe insomnia symptoms: | ||||||
| % Yes | 81.5 | 76.4 | 75.4 | |||
| Mean ± SEM | 1.6 ± 0.01 | -- | 1.5 ± 0.01 | -- | 1.5 ± 0.02 | -- |
| 2006–2010: | ||||||
| % No change | 38.6 | |||||
| % Increase | 26.8 | |||||
| %Decrease | 34.7 | |||||
| 2010–2014: | ||||||
| % No change | 41.3 | |||||
| % Increase | 29.5 | |||||
| %Decrease | 29.2 | |||||
| 2006–2014: | ||||||
| % No change | 37.1 | |||||
| % Increase | 27.1 | |||||
| %Decrease | 35.8 | |||||
| Physician-diagnosed memory problems: | ||||||
| % Memory problems | -- | 3.5 | -- | -- | -- | -- |
| % Dementia | -- | -- | 2.2 | 3.9 | 5.5 | 6.9 |
| % Alzheimer’s disease | -- | -- | 1.9 | 3.1 | 4.2 | 5.1 |
| % Any | -- | 3.5 | 4.2 | 6.7 | 9.0 | 11.0 |
| Dementia diagnosis: | ||||||
| % Yes | -- | 1.6 | 4.3 | 7.1 | 9.7 | 10.8 |