2 PI24 ENDOCRINOLOGA Dislipidemia Prevencin primaria y secundaria

Hipercolesterolemia Familiar y Hiperlipoproteinemias

Clasificación de Hiperlipoproteinemias

• La clasificación de Fredericson categoriza las hiperlipoproteinemias del tipo 1 al 5, excluyendo los tipos 1 y 5 por no presentar riesgo cardiovascular.

• Los tipos más relevantes son la hipercolesterolemia familiar (2A y 2B), siendo la heterocigota la forma más común.

Características de la Hipercolesterolemia Familiar

• La hipercolesterolemia familiar heterocigota presenta niveles de colesterol LDL superiores a 190 mg/dL, lo que requiere tratamiento inmediato.

• En casos homocigotos, el colesterol puede superar los 500 mg/dL con triglicéridos normales, presentando síntomas severos como xantomas tendinosos y tuberosos.

Diferenciación entre Tipos

• La hipercolesterolemia familiar es autosómica dominante y se relaciona con alteraciones en los receptores de LDL; el tipo homocigoto es raro pero severo.

• La hiperlipidemia familiar combinada (tipo 2B) muestra elevaciones tanto en colesterol total como en triglicéridos, también asociándose a enfermedad cardiovascular prematura.

Hipercolesterolemia Poligénica

• Afecta a más del 25% de la población con niveles de colesterol entre 130 y 250 mg/dL; no presenta xantomas ni síntomas típicos de enfermedades familiares.

• Este grupo tiene un riesgo elevado de enfermedad cardiovascular clásica sin ser parte de las hiperlipoproteinemias familiares típicas.

Mecanismos y Manejo Clínico

• Los mecanismos implican defectos en receptores LDL o apo B1 para tipos familiares; disbetalipoproteinemia está relacionada con defectos en apo E (tipo III).

• El manejo principal incluye estatinas para reducir el colesterol endógeno; fibratos solo se utilizan para tratar hipertrigliceridemias severas (>1000 mg/dL) debido al riesgo pancreático.

Statin Therapy Guidelines and Recommendations

High-Intensity Statin Use

• Patients requiring high-intensity statins are typically prescribed atorvastatin or rosuvastatin, with dosage adjustments based on individual assessments.

• The recommended age range for initiating these treatments is between 40 to 75 years; beyond this age, a cost-benefit analysis is necessary.

• A cardiovascular risk greater than 20% indicates a significant mortality risk (1 in 5 over ten years), necessitating high-intensity statin therapy for patients aged 40 to 75.

Risk Assessment and Treatment Decisions

• For patients with a cardiovascular risk between 7.5% and 20%, additional factors such as family history, chronic inflammatory diseases, or elevated triglycerides should be considered before prescribing moderate-intensity statins.

• All diabetic patients over the age of 40 should be treated with statins; those under 75 should receive moderate intensity while those over should receive high intensity.

Primary Prevention Strategies

• Key indicators for primary prevention include LDL levels above 190 mg/dL and cardiovascular risks exceeding 20%. Diabetics also fall into this category regardless of their LDL levels.

• Secondary prevention involves all patients with prior cardiovascular events using statins; those under the age of 75 are advised to use high-intensity statins.

Statin Dosage Guidelines

• Moderate-intensity doses include atorvastatin (10–20 mg/day), rosuvastatin (5–10 mg/day), and simvastatin (20–40 mg/day).

• High-intensity doses consist of atorvastatin (40–80 mg/day) and rosuvastatin (20–40 mg/day). It's important to note that statins are best taken at night due to cholesterol synthesis patterns.

Considerations and Side Effects

• Caution is advised regarding potential side effects such as muscle damage, elevated enzyme levels, or rhabdomyolysis, particularly in older adults.