Antihypertensive Pharmakotherapie und Nierenfunktion bei geriatrischen Notfallpatienten

Zusammenfassung

Fragestellung: Ziel war die Bewertung der Arzneimittelverordnungen und Nierenfunktion bei geriatrischen Notfallpatienten unter besonderer Berücksichtigung der antihypertensiven Therapie.

Patienten und Methodik: Die einjährige Beobachtungsstudie erfolgte bei Patienten aus Pflege- und Altenheimen oder ambulanter Betreuung, die notärztlich behandelt werden mussten. Insgesamt wurden 109 Patienten (85 Frauen) mit einem Durchschnittsalter von 85±8 Jahren eingeschlossen. Auf der Basis von Kreatinin- und Cystatin-C-Serumkonzentrationen wurde die glomeruläre Filtrationsrate (eGFR) mit Formeln errechnet.

Ergebnisse: Die häufigste Akutdiagnose in der Notfallsituation war die Synkope (n = 23), die häufigsten Grunderkrankungen waren Demenz (n = 61) und arterielle Hypertonie (n = 60). Die Gesamtanzahl verschriebener Wirkstoffe betrug 603 (Durchschnitt 5,5 ± 3; Bereich 0 – 13), wobei 65 (60 %) der Patienten ≥ 5 Medikamente täglich erhielten. Von 60 Patienten mit bekannter arterieller Hypertonie wurden 55 (92 %) behandelt, und 71 % erhielten mindestens 2 Antihypertensiva. Die am häufigsten verordneten Wirkstoffe waren ACE-Hemmer (n = 33), Schleifendiuretika (n = 28), Betablocker (n = 22) und Hydrochlorothiazid (n = 15). Die durchschnittlichen Konzentrationen von Kreatinin und Cystatin C waren mit 1,33 ± 0,66 mg/dl und 1,78 ± 0,83 mg/l erhöht. Die Analyse der gemittelten eGFR-Werte zeigte bei bis zu 2/3 der Patienten eine relevante Einschränkung < 60 ml/min/1,73 m² . Bei etwa 30 % der Patienten war die Dosierung im Bezug zur eingeschränkten Nierenfunktion zu hoch.

Folgerungen: Die Verordnung von Antihypertensiva trägt maßgeblich zur Polypharmakotherapie bei geriatrischen Notfallpatienten bei. Bis zu 2/3 dieser Patienten haben eine relevante Nierenfunktionseinschränkung, die zusammen mit der hohen Anzahl an Verordnungen zu dem erhöhten Risiko für unerwünschte Arzneimittelwirkungen und Notfallsituationen beitragen kann.

Summary

Objective: The aim of this study was to assess drug prescriptions and renal function in a cohort of geriatric emergency patients with a focus on antihypertensive drug treatment.

Patients and methods: The one-year observational study was conducted among patients from nursing and retirement homes or outpatient care who were treated by the emergency medical service. Overall, 109 patients (85 women, mean age 85±8 years) were studied. Glomerular filtration rate was estimated (eGFR) on the basis of creatinine and cystatin C serum concentrations.

Results: The most common emergency admission diagnosis was syncope (n = 23), while the most common clinical diagnoses were dementia (n = 61) and hypertension (n = 60). Overall, 603 drugs were prescribed (mean 5.5 ± 3, range 0 – 13), with 65 patients (60 %) receiving ≥ 5 drugs per day. Of 60 patients with the known diagnosis of hypertension 55 (92 %) were being treated, while 71 % received at least 2 antihypertensive drugs. ACE-inhibitors (n = 33), loop diuretics (n = 28), beta-blockers (n = 22) and hydrochlorothiazide (n = 15) were the most frequently prescribed drugs. Mean creatinine (1.33 ± 0.66 mg/dl) and cystatin C (1.78 ± 0.83 mg/l) concentrations were elevated. Overall, up to two thirds of patients had eGFR values of < 60 ml/min/1.73 m². In up to 31 % of patients dosages were too high in relation to renal dysfunction.

Conclusions: The prescription of antihypertensive drugs contributes significantly to polypharmacy in geriatric emergency patients. About two thirds of these patients had clinically relevant impairment of renal function. The latter, together with the high number of prescribed drugs, may expose geriatric patients to an increased risk of adverse drug reactions requiring emergency treatment.

Schlüsselwörter

Ältere - Nierenfunktion - unerwünschte Arzneimittelwirkungen - arterielle Hypertonie - Dosierung von Antihypertensiva - Polypharmakotherapie

Keywords

elderly - renal function - adverse events - hypertension - anithypertensive drug dosage - polypharmacy

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