Hypertension: severe: renal causes were common.

Clinical bottom line (level 4)

  1. Around a third of patients with severe hypertension and grade III or IV retinopathy had renovascular hypertension.
Davis et al: New England Journal of Medicine 1979; 301 (23): 1273-1276
Expires August 2003

The study

Case series with objective outcomes, not adjusted for confounding factors, not validated in an independent set of patients.

Setting: university hospital, USA

123 patients (aged mean 44 years, 51% male) with severe hypertension (diastolic blood pressure > 125 mmHg) and Grade III or IV hypertensive retinopathy (flame haemorrhages, soft cotton-wool exudates or papilledema)

Excluded if
  • evidence of primary renal parenchymal disease (e.g. dialysis patients)
  • admitted to paediatric or obstetric services





    • Outcomes studied:
  • renovascular hypertension (from patients who had renal arteriography)

    • 76% of patients had renal arteriography. Considered positive if:
      • > 25 % atherosclerotic narrowing in a segmental or main renal artery
      • fibromuscular dysplasia
    • Patients with renal-artery disease had renin assays and differential renal-excretory studies: if either showed lateralisation, the test was considered to indicate renovascular hypertension.

    The evidence

    outcome time to outcome number of patients/total number %
    (95% CI)
    renovascular hypertension ? 28/93 30%
    (21% to 39%)

    Comments

    1. Patients who did not have arteriography were more likely to have elevated creatinine levels, suggesting that the prevalence found may be an underestimate.
    2. The study would be more useful if it also commented on the prevalence in patients with hypertension and grade I or II retinopathy.

    Citation

    1. Davis BA, Crook JE, Vestal RE, et al: prevalence of renovascular hypertension in patients with grade III or IV hypertensive retinopathy. New England Journal of Medicine 1979; 301 (23): 1273-1276
    Contributor: Chris Ball and Clare Wotton, August 2000
    Reviewer:

    Clinical Question.
    Patient severe hypertension
    Intervention or Exposure prevalence
    Outcome renovascular hypertension