For an asymptomatic patient with new-onset stage 1 or lower level stage 2 hypertension, a serum creatinine, lipid profile (preferably fasting), glucose (preferably fasting), potassium, routine urinalysis, and ECG are clinically justifiable and cost-effective, according to a case study published in the January issue of the Journal of Clinical Hypertension.
Joel Handler, MD, of Kaiser Permanente in Anaheim, Calif., presented the case of a 56-year-old man who went to his physician because of an aching shoulder and was found to have blood pressure (BP) readings of 156/78 mm Hg and 154/82 mm Hg. His physical examination revealed a weight of 101.6 kg, height of 172.7 cm (body mass index (BMI), 34 kg/m2), heart rate of 78 beats per minute and localized tenderness over the left shoulder. Painful abduction was demonstrated and a diagnosis of subacromial bursitis was made. He received a cortisone injection and was asked to return in two weeks.
Otherwise, the patient felt well and had not previously seen a physician in many years. At the time of his follow-up visit, the shoulder bursitis had resolved and a repeat BP reading was 152/76 mm Hg. On a weight reduction and regular walking program, his BP one month later was 154/82 mm Hg. A systems review did not reveal complaints, and the physical examination showed normal optic fundi, normal chest and cardiac examination, no abdominal masses or bruits, and intact peripheral pulses without bruits. He denied a family history of diabetes mellitus or coronary heart disease. Creatinine, lipid profile, glucose, potassium, routine urinalysis and ECG were ordered.
Handler said at this point, it is reasonable to obtain baseline laboratory testing anticipating initiation of antihypertensive therapy.
Although a few more months of lifestyle modification would be an option for a patient with stage 1 BP, chronic hypertension is the best explanation for the observation that serial BPs over six weeks did not show any regression to the mean effect, according to Handler. Also, the patient’s age places him in a class which could lend to additional subclinical cardiovascular comorbidities. According to various trials, BP control <140/90 mm Hg within a few months was associated with significantly reduced risk of stroke and myocardial infarction (MI) in patients 55 years and older with additional cardiovascular risk factors. Therefore, laboratory evaluation is indicated at this time while continuing to pursue lifestyle modification and initiation of drug therapy.
The patient described has three risk factors for diabetes mellitus: age older than 45 years; BMI greater than, equal to 25 kg/m2; and hypertension – a common triad.
Handler said that when considering screening tests for large populations, cost-effective analysis is worthwhile. A Markov model analysis considered targeted screening for type 2 diabetes mellitus for patients with hypertension recommended by the 2003 U.S. Preventative Services Task Force. In 1997, a $24 expense for each hypertensive patient screened with a fasting glucose would cost $87,096 for one quality-adjusted life year (QALY) starting at age 35, and $46,881 for one QALY starting at age 45. The authors recommended screening limited to hypertensive patients aged 55 to 75 years at a cost of $34,375 for one QALY.
Renal status is important to assess with regard to estimating global cardiovascular risk; deciding goal BP; ruling out primary renal disease as a cause of hypertension; and establishing a baseline before initiating antihypertensive therapy, which may affect renal function, according to Handler.
He also wrote that a baseline ECG is important to assess subclinical cardiac disease, because asymptomatic coronary artery disease would change medication management and alter goal BP. Silent MIs by ECG made up 25 percent of total MIs and were as likely to lead to death, heart failure and stroke as clinical MIs in both the Framingham Heart Study and the Multiple Risk Factor Intervention Trial (MRFIT).
While primary hyperparathyroidism is associated with hypertension, parathyroidectomy is not expected to cure hypertension in these cases, Handler said. Hypercalcemia due to primary hyperparathyroidism is a thiazide contraindication but is rare, and a cost-effective analysis of routine test ordering for all patients with hypertension has not been performed, according to Handler. He said obtaining a serum calcium value may be more ideally positioned further down the line