The use of antihypertensive therapy in Spain (1986-1994)

[Pharmacological compliance in the treatment of arterial hypertension. A review of studies published between 1975 and 2011]

A systematic review was performed from published articles on compliance (PubMed), between 1975 and first of June 2011. Specifically those which measured medication adherence using indirect methods (RCS and/or MEMS-Medication Event Monitoring System) were searched. Descriptors used were: hypertension AND patient compliance AND medication adherence. The main objective is to update the topic of therapeutic compliance in arterial hypertension worldwide, with special attention to Spain, as well as a critical evaluation of the evolution of therapeutic compliance over the period 1975-2011. After analysing 37 research studies published worldwide, the results were: total number of 8623 hypertensive patients, of whom 25.62% were non-compliers (n=2209; 95% CI; 23.82-27.42), and 74.38% were compliers (n=6414; 95% CI; 73.32-75.44). The weighted average of non-compliance was 37.60%. We conclude that the default rate in the pharmacological treatment of hypertension worldwide is high.

[Use of prescription drugs in Spain and Europe]

OBJECTIVE

To compare the Spanish prescription drug consumption with that of European countries.

DESIGN

A review of the literature and data sources for prescription drug consumption.

SETTING

European countries; last three decades.

PARTICIPANTS

Included therapeutic groups where the available information allowed a comparison of the consumption in Spain with that of other European countries.

MEASUREMENTS

Studies, reports, or data sources were included in which the consumption was expressed in DHD (DDD/1000 inhabitants per day).

RESULTS

It was possible to compare 18 therapeutic groups: drugs for peptic ulcer (A02B), glucose lowering drugs (A10), antithrombotic agents vitamin K antagonists (B01AA), antihypertensives (C02), diuretics (C03), peripheral vasodilators (C04), beta-blocking agents (C07), calcium channel blockers (C08), agents acting on the renin-angiotensin system (C09), lipid-lowering drugs (C10), antibacterials for systemic use (J01), antiinflammatory & antirheumatic products non-steroids (M01A), opioid analgesics (N02A), antipsychotics (N05A); anxiolytics (N05B), hypnotics & sedatives (N05C), antidepressants (N06A) and drugs for obstructive airway diseases (R03). With regard to the European average (100), the Spanish consumption of these therapeutic groups was: N02A, 37; C07, 40; B01AA, 41; C03, 70; N05C, 72; C10, 75; C08, 76; N05A, 77; TH01, 97; N06A, 98; C09, 104; M01A, 101; R03, 101; C02, 107; A10, 114; N05B, 137; A02B, 150 and C04, 234.

CONCLUSIONS

The Spanish consumption of most of the therapeutic groups was very close to the average of the group of the countries where it was possible to compare it, or clearly below average, with the exception of the consumption of drugs for peptic ulcer, anxiolytics and peripheral vasodilators, which considerably exceeded the average of the group.

Roles of human urotensin II in volume resistance hypertension in peritoneal dialysis patients

Human urotensin II (hUII) is a newly discovered substance that can dilate small blood vessels to decrease the blood pressure (BP). Our previous studies showed that some volume-overloaded patients on peritoneal dialysis can maintain normal BP (congestive heart failure excluded), suggesting that these patients have volume resistance capacity. This study is to investigate whether hUII plays an important role in this subgroup of patients on peritoneal dialysis. In this study, 105 patients on continuous ambulatory peritoneal dialysis were enrolled. Volume load was evaluated by the overhydration (OH) value obtained by bioimpedance analysis. OH < 2.0 kg was defined as normal volume (NV), and OH ≥ 2.0 kg as high volume (HV). Systolic blood pressure (SBP) <130 mmHg was defined as normotension (NT) and ≥130 mmHg as hypertension (HT). The patients were thus divided into four subgroups: (1) normotension with normal volume (NT-NV), (2) normotension with high volume (NT-HV), (3) normal volume with hypertension (HT-NV), and (4) high volume with hypertension (HT-HV). hUII was measured using radioimmunoassay method. hUII was significantly higher in normal SBP group than that in high SBP group (p < 0.05). hUII was higher in the NT-HV group compared with that in the HT-HV group (p < 0.05). Our study suggests that hUII may be involved in the pathogenesis of the volume resistance HT in peritoneal dialysis patients.

Metabolic syndrome and its components associated with endothelial dysfunction in chronic kidney disease patients

BACKGROUND

Cardiovascular disease is more common in patients with chronic kidney disease (CKD) than in the general population. Endothelial dysfunction is an early predictor of cardiovascular events.

OBJECTIVE

We conducted a cross-sectional study in CKD patients to explore the association of metabolic syndrome (MetS) components with endothelial cell function.

METHODS

We evaluated clinical and laboratory data in 161 CKD patients from stage 1 to stage 5. Endothelial function was estimated by flow-mediated dilatation (FMD) of the brachial artery and expressed as percentage change relative to baseline diameter. MetS was defined according to the National Cholesterol Education Program-Adult Treatment Panel III criteria.

RESULTS

Patients were grouped into two groups according to whether or not they had MetS. FMD was significantly lower in the MetS group than in the group without MetS (P = 0.012). In a Pearson's correlation analysis, FMD was significantly negatively correlated with waist circumference in women (r = -0.223, P = 0.03) and fasting blood glucose (r = -0.186, P = 0.001). Multiple linear regression analysis showed that fasting blood glucose was an independently associated factor for FMD.

CONCLUSION

MetS and some components of MetS (waist circumference in women and fasting blood glucose) are closely associated with a decreased FMD in CKD patients.

Antihypertensive drugs utilisation and educational activities

The mortality rate from cardiovascular diseases is high in Serbia. Analysis of antihypertensive drugs utilization is the basis for assessment of cardiovascular pharmacotherapy appropriateness. The aim of this study was to analyze the trend in antihypertensive drugs utilization among outpatients in Niš region, South Serbia compared to some Nordic countries (Norvay, Sweden) and Australia as well as to analyze trends in educational and drug promotion activities directed to primary healthcare workers within the same region. Using the ATC/DDD methodology, we analyzed the utilization of antihypertensive drugs dispensed on prescription in the Nis region over the 2003–2007 period. The study was retrospective, based on data obtained from Central City Pharmacy Nis. Educational and drug promotion activities were noted from the records of Medical Faculty, University of Nis, and from the records of local branches of pharmaceutical companies active in Serbia. Wilcoxon’s test was used in order to calculate the statistical significance of difference. A significant increase of 79.8% (153.8/ 276.6 DDD/inhabitants/day) in antihypertensive drug consumption was observed in the same period. This analysis showed there were substantial increases in the use of diuretics (134.7%), ACE inhibitors (79.5%) and calcium channel blockers (116.1%), especially amlodipin (241.2%). During the observed period, annual numbers of educational activities and of pharmaceutical sales representatives employed within the region increased for almost one fourth. This analysis pointed to a significant increase in the use of antihypertensive drugs in the Nis region, which was matched with increase in educational and drug promotion activities within the region, so that in 2006–2007 total consumption was approximate to some referential countries (Norvay, Sweden).

Peripheral Resistance Modulates the Response to Volume Overload in Peritoneal Dialysis Patients

Background

Volume overload is thought to be the most important cause of hypertension in peritoneal dialysis (PD) patients. However, there is also evidence that normalization of volume overload is not always accompanied by a drop in blood pressure (BP). In the present study, we hypothesized that dysregulation of peripheral resistance due to endothelial dysfunction would constitute an important determinant of BP response in overhydrated PD patients.

Methods

We performed an observational, prospective cohort study including all prevalent PD patients at the Peking University Third Hospital between 1 June 2006 and 30 November 2006. After baseline measurements, including echocardiography and bioelectrical impedance analysis, patients fulfilling inclusion criteria were reevaluated after 2 months of follow-up. All patients that exhibited significant changes in BP and extracellular water (ECW) between 2 visits were asked to undergo a second ultrasound. These patients were then divided into group A (parallel change between BP and ECW; n = 12) and group B (paradoxical change between BP and ECW; n = 10).

Results

The cohort included 22 patients (13 males) with a mean age of 59 ± 13 years, on dialysis for 23.3 ± 32.6 months. There were no baseline differences between groups A and B. However, while patients in group A significantly increased their cardiac output, total peripheral resistance remained stable. In group B, cardiac output did not change significantly but total peripheral resistance decreased significantly.

Conclusion

In PD patients, a significant increase in fluid volume is not necessarily linked to a significant increase in BP. Rather, the change in total peripheral resistance was found to be the most important determinant of the extent to which increased fluid volume affected BP.

Why is there significant overlap in volume status between hypertensive and normotensive patients on dialysis?

BACKGROUND/AIM

Volume overload is believed to play a pivotal role in the pathogenesis of hypertension in dialysis patients. Although the extracellular water (ECW) content in hypertensive dialysis patients was significantly higher than in normotensive dialysis patients on the whole, there was considerable overlap in ECW between the two groups. Little is known about the hemodynamic characteristics in subgroups of patients with normotension but a high volume (HV) status or with hypertension but a normal volume (NV) status. We investigate the overlap in ECW between controlled and uncontrolled hypertension in dialysis patients.

METHODS

Fifty-two patients (mean age 62 years, 26 males and 26 females) on peritoneal dialysis were enrolled into this study. The ECW was assessed by bioimpedance analysis and normalized by individual height in meters (NECW). The mean value of NECW in both sexes was arbitrarily set to define NV status (lower than mean value) or HV status (higher than mean value). All patients were thus divided into four subgroups: controlled hypertension with NV (CHT-NV), controlled hypertension with HV (CHT-HV), uncontrolled hypertension with NV (UHT-NV) and uncontrolled hypertension with HV (UHT-HV). The stroke volume, cardiac output and total peripheral resistance were echocardiographically measured and their respective indices were calculated.

RESULTS

There were 12 (23%), 8 (15%), 14 (27%) and 18 (35%) patients in the CHT-NV, CHT-HV, UHT-NV and UHT-HV subgroups, respectively. The four subgroups were matched for sex, diabetes and age. The NECW in the CHT-HV group was higher than that in CHT-NV and UHT-NV groups (p < 0.01), but was comparable with that in the UHT-HV group. The stroke volume and cardiac output indices in the CHT-HV group were not significantly different from those in the CHT-NV and UHT-NV groups. The total peripheral resistance index in the CHT-HV group was lower than that in UHT-NV and CHT-NV groups (p < 0.05), but was comparable to that in the UHT-HV group. There was no difference in heart rate among the four groups.

CONCLUSIONS

The overlap in ECW between controlled hypertension and uncontrolled hypertension in dialysis patients was related to a significant difference in total peripheral resistance index, but not to significant differences in stroke volume and cardiac output indices. The CHT-HV patients were characterized by lower total peripheral resistance indices.

Effects of essential medicines on cardiovascular products available for the market in Thailand

National List of Essential Medicines (NLEM) is an important policy on drugs, which also covers the drug availability. However, the link between the list and the availability of medicine products for the market is not clear. The objectives of this study were to examine the effects of essential medicines (EM) on the patterns and values of cardiovascular products available for the market in Thailand. Issues investigated were proportions of products, expansions of generic names, involvement of producers and relation between the numbers of EM generic names and production values of products. Data sources were NLEM, Thailand Index of Medical Specialities and drug statistics by Food and Drug Administration (FDA). Results revealed the availability of 623 products from 127 generic names. On average, EM products showed significantly greater proportions and EM generic names demonstrated larger expansions than non-EM. Domestic producers contributed to List A products by a significantly higher percentage than foreign, but only foreign producers introduced List D products. There was a positive and significant relation between the numbers of EM generic names and the production values of products. In conclusion, it was clear that EM had effects on the patterns and the values of cardiovascular products available for the market. Subsequent prices and expenditure due to the patterns and values of product availability could be low or high. These findings could be advantageous in using essential medicines as a means to avoid the negative consequences by addressing the significance of its kinds and numbers when selecting it in the list.

Equipotent doses of transdermal fentanyl and transdermal buprenorphine in patients with cancer and noncancer pain: results of a retrospective cohort study

BACKGROUND

The equipotency ratio of transdermal (TD) fentanyl to oral morphine has been established as 1:100; for buprenorphine TD, a ratio of 1:75 has been proposed, although this ratio has not been confirmed in clinical studies. Growing evidence from clinical practice, in which much lower doses of buprenorphine are used, suggests that this conversion ratio may be too high.

OBJECTIVE

The aim of this study was to compare calculated equipotent oral morphine doses of fentanyl TD with equipotent oral morphine doses of buprenorphine TD prescribed in clinical practice.

METHODS

This retrospective study identified patients with cancer and noncancer pain who had received > or =1 prescription for fentanyl TD or buprenorphine TD (the all-patients groups) from the German IMS Disease Analyzer-mediplus database, which contains all relevant data concerning drug prescriptions from 400 practices in Germany. Also identified were subgroups of the all-patients groups who had received long-term treatment with fentanyl TD or buprenorphine TD and were considered to have similar pain intensity, as they had previously received similar analgesic medication (the identical-cohort groups). Mean prescribed daily doses for the all-patients and identical-cohort groups were calculated based on the distribution of prescribed patch strengths. Because patients could have applied >1 patch, mean prescribed daily doses were also calculated based on an assumption of double application when appropriate. Equipotent oral morphine doses were estimated using equipotency ratios of 1:100 for fentanyl TD and 1:75 for buprenorphine TD.

RESULTS

The all-patients groups consisted of 2198 patients with noncancer pain and 2544 patients with cancer pain; the identical-cohort groups consisted of 380 patients with noncancer pain and 496 patients with cancer pain (529 women, 347 men; mean age, 74 years [range, 25-101 years]). Equipotent doses of oral morphine were significantly lower in patients receiving buprenorphine TD compared with those receiving fentanyl TD (P < 0.001). In cancer patients, the equipotent oral morphine doses of fentanyl TD and buprenorphine TD were 130.9 to 138.9 mg and 85.2 to 88.8 mg, respectively; in noncancer patients, the corresponding values were 117.0 to 118.3 mg and 80.2 to 80.9 mg. Based on these results, an equipotency ratio of 1:110 to 1:115 for buprenorphine TD would appear to be more appropriate than the proposed ratio of 1:75.

CONCLUSIONS

The fact that this retrospective analysis conducted in identical cohorts showed lower calculated equipotent oral morphine doses in the buprenorphine TD groups compared with the fentanyl TD groups calls into question the proposed 1:75 ratio for conversion of buprenorphine TD to equipotent oral morphine doses. Based on the findings of the present study, an equipotency ratio of 1:110 to 1:115 may be more appropriate. However, confirmative data from prospective randomized clinical trials are needed.

Uso de antihipertensivos en Cantabria (1995–2002): el desfase con las evidencias

OBJECTIVE

To ascertain the pattern of prescription of antihypertensive drugs in Cantabria and its variation from published evidence between 1995 and 2002.

METHOD

We reviewed the database of the pharmaceutical data processing system of the Cantabrian Health Service on the consumption and cost of the drugs indicated in the treatment of hypertension. Consumption data is expressed in defined daily doses per thousand inhabitants and day (DID).

RESULTS

Consumption of antihypertensive agents was 130.2 DID in 1995 and was 235 DID in 2002. The contribution of diuretics to overall consumption fell from 34.3% in 1995 to 25.8% in 2002, and that of beta-blockers fell from 6.5% in 1995 to 5.9% in 2002. The most commonly used group in all years was angiotensin converting-enzyme inhibitors, which represented 36.8% of consumption in 2002. Angiotensin-II antagonists showed the biggest rise, accounting for 13.2% of prescriptions in 2002 and for 26% of expenditure on antihypertensive agents. The pattern of use of the drugs utilized in the major published trials during this period showed no change or even fell, except in the case of enalapril.

CONCLUSIONS

The present study confirms that the prescription antihypertensive drugs has considerably increased and that the consumption pattern of these drugs has changed. The discrepancy between these findings and those of the major trials could have significant economic implications.