Office hypertension in type 2 (non-insulin-dependent) diabetic patients

Prognostic significance of the white coat hypertension in patients with type 1 diabetes mellitus

Despite the high prevalence of white coat hypertension (WCH) in diabetes mellitus and the evidence that hypertension is a clear risk factor for the development of microalbuminuria (MA) in these patients, there is no information on the long-term prognostic significance of this condition in the diabetic population. We studied the evolution of 40 patients with type 1 diabetes mellitus (Type 1 DM). Twenty patients with WCH (office blood pressure> or =140/90mmHg associated with mean daytime blood pressure<135/85mmHg) classified as the WCH group and 20 patients with type 1 DM with a similar age and disease evolution, but who were normotensive, (office blood pressure<140/90mmHg associated with mean daytime blood pressure<135/85mmHg) classified as the normotensive control group. After 5 years of follow-up, MA appeared in four subjects and sustained hypertension in another, with a total of 31% of events in the WCH group, with none in the normotensive group. Kaplan-Meier analysis showed that the relative risk of developing these hypertensive events was 25% higher in the WCH group. At baseline, the night time systolic and diastolic blood pressure levels were significantly higher in patients who further developed MA and sustained hypertension. The findings in this study highlight the clinical importance of careful follow-up of type 1 diabetic patients with WCH.

Usefulness of home blood pressure measurement in the morning in type 2 diabetic patients

OBJECTIVE

Recently, repeated home blood pressure (HBP) measurements in the morning for a long period have been shown to have a stronger predictive power for mortality in patients with hypertension than occasional casual/clinic blood pressure (CBP) measurements. We studied whether HBP in the morning in type 2 diabetic patients is useful for prediction of diabetic complications.

RESEARCH DESIGN AND METHODS

The occurrence of diabetic complications (nephropathy, retinopathy, coronary heart disease [CHD], and cerebrovascular disease [CVD]) were examined in relation to morning HBP as well as to CBP in 170 type 2 diabetic patients treated with antidiabetic and antihypertensive drugs. Blood pressure was measured at the clinic during the day and at home after awakening in the morning. Clinic hypertension (CH) and morning hypertension (MH) were defined as systolic blood pressure (SBP) > or =130 mmHg and/or diastolic blood pressure (DBP) > or =85 mmHg. The relation of CH and MH to the prevalence of these events was examined.

RESULTS

There were no significant differences in the prevalence of nephropathy, retinopathy, CHD, and CVD between the two groups with (n = 131) and without CH (n = 39), whereas the prevalences of these events in the patients with MH (n = 97) were significantly higher (P < 0.05) than in those without MH (n = 73). The prevalence of nephropathy was highly associated with systolic MH.

CONCLUSIONS

Elevations of HBP in the morning in diabetic patients are strongly related to microvascular and macrovascular complications, especially nephropathy. It is concluded that the control of MH may prevent vascular complications in type 2 diabetic patients.

White coat hypertension in type 1 diabetic patients without nephropathy

The aim of our study was to determine the prevalence of white coat hypertension (WCH) in type 1 diabetic patients. Therefore, ambulatory blood pressure monitoring (ABPM) and 24-h urinary albumin excretion (UAE) were determined in 47 patients with type 1 diabetes mellitus (27 with new diagnosis of hypertension by office blood pressure (BP) measurement and 20 with normotension). WCH was diagnosed in 20 patients (74%). Patients with WCH presented higher values of systolic and diastolic BP and UAE than normotensive patients. The results indicate that in type 1 diabetes mellitus WCH is very frequent. Thus, WCH may represent a potential risk for the development of diabetic complications, mainly diabetic nephropathy.

Value of blood pressure self-monitoring as a predictor of progression of diabetic nephropathy

OBJECTIVE

To determine the impact of self-monitoring of blood pressure values (BP(S)) as compared with office blood pressure measurements (BP(O)) on the progression of diabetic nephropathy.

DESIGN

Long-term, follow-up cohort study.

SUBJECTS AND METHODS

Hypertensive, type 1 diabetic patients with overt diabetic nephropathy were investigated. Patients initially participated in a hypertension treatment and teaching programme including extensive advice on blood pressure self-monitoring. Self-monitoring and office blood pressure values were continuously assessed during the entire follow-up period. Progression of diabetic nephropathy over the study period was individually assessed as the mean decline of glomerular filtration rate (GFR) per patient per year. Baseline and follow-up parameters were included in stepwise multiple regression analyses with the decline of GFR per year as the dependent variable.

RESULTS

Seventy-seven type 1 diabetic patients (37 women, 40 men) were followed for a mean period of 6.2 +/- 2.8 years (mean +/- SD; range 2-12) resulting in a total of 481 patient-years. During the follow-up period, mean BP(O) decreased from 166/95 at baseline to 154/89 mmHg during follow-up, and mean BP(S) fell from 159/93 to 138/83 mmHg. The mean decline of GFR was 4.1 +/- 5.6 ml/min per year. Loss of kidney function was significantly correlated with proteinuria, blood pressure and glycosylated haemoglobin values. In the multiple regression analyses, BP(S) predicted the loss of renal function better than BP(O) (R2 = 0.52 versus 0.42). The simple correlation between BP(S) and GFR decline was higher compared to BP(O) and GFR (r = -0.42; P < 0.0001 versus -0.33; P < 0.004).

CONCLUSION

Blood pressure self-monitoring values are a better predictor of progression of diabetic nephropathy when compared with office blood pressure measurements.

White coat hyperglycaemia: disparity between diabetes clinic and home blood glucose concentrations

OBJECTIVES

To identify patients with discrepantly high clinic blood glucose concentrations compared with self reported values and to assess whether such patients have errors in self monitoring technique. To determine whether, in patients with good technique, the discrepancy is a transient phenomenon related to clinic attendance.

DESIGN

Prospective study of diabetes clinic patients recruited over six months.

SETTING

Outpatient diabetes clinic of a teaching hospital.

SUBJECTS

34 consecutive patients with non-insulin dependent diabetes who had had at least two consecutive clinic blood glucose concentrations more than 5 mmol/l higher than the mean self reported concentration.

MAIN OUTCOME MEASURES

Assessment of monitoring technique; presence of cognitive or physical impairment; serum fructosamine concentration; home and clinic blood glucose concentrations.

RESULTS

15 of 34 patients had errors in monitoring technique, 12 of whom had cognitive or physical impairment. In the remaining 19, the mean (SD) blood glucose concentrations of capillary and venous samples taken at home (10.2 (0.6) and 12.2 (1.1) mmol/l respectively) were significantly lower than in those taken at the clinic (16.8 (1.6) mmol/l, p < 0.0002). The fructosamine concentration was significantly higher in patients with monitoring errors than those without (2.4 (0.4) v 1.8 (0.4) mmol/l, p < 0.0001).

CONCLUSIONS

"White coat" hyperglycaemia was detected in about half the patients but errors in technique accounted for the rest of the discrepancies. Patients' ability should be assessed before teaching self monitoring and the technique checked regularly.