Table 2. Adjusted Multivariable Cox Proportional Hazards Regression Models for Incidence of Dementia or Mild Cognitive Impairmenta.
Characteristic | No. | HR (95% CI) | P value |
---|---|---|---|
Probable dementia | |||
Objective visual impairment in either eye | |||
20/40 or worseb | 183 | 2.14 (1.08-4.21) | .03 |
20/80 or worsec | 31 | 5.20 (1.94-13.95) | .001 |
20/100 or worsed | 21 | 5.66 (1.75-18.37) | .004 |
Subjective visual impairmente | 206 | 1.22 (0.56-2.66) | .61 |
Mild cognitive impairment | |||
Objective visual impairment in either eye | |||
20/40 or worseb | 183 | 1.84 (0.90-3.78) | .10 |
20/80 or worsec | 31 | 5.62 (1.94-16.33) | .002 |
20/100 or worsed | 21 | 6.43 (1.66-24.85) | .007 |
Subjective visual impairmente | 206 | 1.30 (0.61-2.77) | .50 |
Both mild cognitive impairment and dementia | |||
Objective visual impairment in either eye | |||
20/40 or worseb | 183 | 1.74 (1.02-2.97) | .04 |
20/80 or worsec | 31 | 4.42 (1.95-10.03) | <.001 |
20/100 or worsed | 21 | 5.54 (2.02-15.16) | <.001 |
Subjective visual impairmente | 206 | 1.27 (0.71-2.27) | .42 |
Abbreviations: HR, hazard ratio; 3MS, Modified Mini-Mental State Examination; WHISE, Women’s Health Initiative Sight Exam.
Twelve separate regression models were evaluated in total, assessing 3 outcomes of interest (probable dementia, MCI, and either probable dementia or MCI) and evaluating visual impairment as a risk factor defined in 4 different ways: objective visual impairment of 20/40 or worse, objective visual impairment of 20/80 or worse, objective visual impairment of 20/100 or worse, and presence of subjective visual impairment. Regression models adjusted for age, race/ethnicity, hormone therapy (based on trial arm), self-reported educational level, self-reported physical activity, self-reported hearing loss, smoking status, 3MS Score at WHISE baseline, and self-reported systemic comorbidities (depression, cardiovascular disease, congestive heart failure, hypertension, hyperlipidemia, chronic pulmonary disease, peptic ulcer disease, liver disease, leukemia or lymphoma, and diabetes).
Reference group: better than 20/40 visual acuity in either eye.
Reference group: better than 20/80 visual acuity in either eye.
Reference group: better than 20/100 visual acuity in either eye.
Reference group: no subjective visual impairment.