Tighter blood pressure control showed no clear cognitive benefit
Dementia or mild cognitive impairment occurred at 3.69 versus 3.89 events per 100 person-years with intensive versus standard treatment over a median 3.8 years.
Our read
Interventions- Studied:
- Randomized trial in 12,434 adults with type 2 diabetes, against standard blood pressure treatment (Blinded, multicenter, sample size calculated, registered NCT03808311)
- What changed:
- Dementia or mild cognitive impairment showed no clear difference with intensive versus standard blood pressure treatment (hazard ratio 0.96)
- The catch:
- Missed mild cognitive impairment at baseline could dilute the apparent treatment effect
- In the record:
- The 65th paper on intensive blood pressure control with results in people; 84 on record in all.
Editor of record: Boris Djordjevic · AgingResearch.News
Adults in China aged 50 or older with type 2 diabetes, raised blood pressure and increased cardiovascular risk took part in a randomized controlled trial. This prespecified cognitive analysis included 12,434 participants without probable dementia at entry; 44.8% were women. Treatment targeted systolic pressure—the upper blood pressure number—below 120 or below 140 millimeters of mercury for up to five years. Cognitive assessors did not know treatment assignments.
Over a median 3.8 years, intensive treatment did not clearly reduce the combined occurrence of dementia or mild cognitive impairment, problems with thinking or memory less severe than dementia. The range of likely effects included no difference. In a brain-scan subset, intensive treatment was associated with a smaller increase in the volume of white matter lesions, abnormal areas in the brain’s nerve-fiber tissue.
Why it matters
For adults with type 2 diabetes, the trial addressed whether tighter blood pressure targets could help preserve thinking and memory as they age.
Caveats
The authors note that participants and treating doctors knew the treatment assignments, which could have influenced care or expectations. The analysis excluded people with probable dementia at entry and included only adults in China.
From the paper
- Participants
Among 1357 participants randomised at the 10 clinical centres included in the MRI study, 862 completed a baseline MRI scan and constituted the MRI substudy population (428 intensive treatment v 434 standard treatment; fig 5).
- Follow-up
During a median follow-up of 3.8 (IQR 2.4-4.5) years, 93.2% (11 583/12 434) of participants completed at least one post-randomisation cognitive assessment (5791 intensive treatment v 5792 standard treatment).
- Result
No statistically significant between group difference was observed (hazard ratio 0.96, 95% CI 0.86 to 1.06; P=0.38) (table 2 and fig 3).
- Limitation
Firstly, open label trials are vulnerable to risks of performance bias, cointervention bias, and expectation effects.
Quoted word for word from the full text on bmj.com.
Comments
Be the first to comment.