Section 1.3: Risk Assessment and Stratification

Risk Assessment and Stratification

Clinical risk assessment is a foundational competency for the FNP, enabling the transition from reactive treatment to proactive prevention. Prevention is conceptualized in three tiers:

• Primary Prevention: Interventions designed to prevent the onset of disease (e.g., immunizations, counseling on tobacco cessation).
• Secondary Prevention: Early detection of asymptomatic disease to initiate early treatment (e.g., screening mammograms, Pap smears, colonoscopies).
• Tertiary Prevention: Management of established disease to minimize complications and optimize function (e.g., cardiac rehabilitation post-myocardial infarction, diabetic foot care).

To allocate preventive resources effectively, the FNP must utilize validated risk stratification tools to quantify a patient’s specific probability of future clinical events.

Familial and Genetic Risk Assessment

A complete three-generation pedigree is the primary tool for identifying hereditary risk factors. In primary care, the FNP must screen for hereditary cancer syndromes and genetic cardiovascular conditions (e.g., familial hypercholesterolemia). Red flags that warrant a referral to a genetic counselor include:

• Multiple relatives on the same side of the family with the same or related cancers (e.g., breast, ovarian, and pancreatic cancers).
• Cancer diagnosed at an unusually young age (e.g., breast or colon cancer diagnosed before age 50).
• An individual with multiple primary cancers (e.g., bilateral breast cancer).
• A relative with a known high-risk genetic mutation (e.g., BRCA1, BRCA2, or MLH1/MSH2 associated with Lynch syndrome).

Behavioral Risk Assessment

Behavioral risk factors, such as tobacco use, alcohol misuse, and sedentary lifestyles, are modifiable drivers of chronic disease.

• Tobacco Use: Screen all patients at every visit using the "5 As" framework: Ask about use, Advise to quit, Assess willingness to make a quit attempt, Assist in the quit attempt (pharmacotherapy/counseling), and Arrange follow-up.
• Alcohol Misuse: Screen using the CAGE questionnaire. A score of 2 or more indicates a high likelihood of alcohol abuse or dependence and warrants further evaluation. For a more comprehensive screening, the Alcohol Use Disorders Identification Test (AUDIT) is utilized.
• Adolescent Substance Use: The CRAFFT screening tool is validated for patients under 21, assessing behaviors related to riding in a Car with an impaired driver, using substances to Relax, using Alone, Forgetting things while using, Family/Friends advising to stop, and getting into Trouble.

Clinical Risk Stratification Tools

The FNP must be proficient in utilizing and interpreting objective clinical calculators to guide pharmacological interventions:

• ASCVD Risk Estimator Plus (ACC/AHA): Estimates 10-year risk of an atherosclerotic cardiovascular disease event (myocardial infarction or stroke) for individuals aged 40 to 79. It incorporates age, sex, blood pressure, cholesterol levels, diabetic status, smoking history, and antihypertensive therapy.
  • Low Risk (<5%): Focus on lifestyle modifications.
  • Borderline Risk (5% to <7.5%): Discuss risk-enhancing factors (e.g., family history of premature ASCVD).
  • Intermediate Risk (7.5% to <20%): Initiate moderate-intensity statin therapy.
  • High Risk (>=20%): Initiate high-intensity statin therapy to reduce LDL-C by 50% or more.
• FRAX (Fracture Risk Assessment Tool): Calculates the 10-year probability of a major osteoporotic fracture and hip fracture. It is indicated for postmenopausal women and men aged 50 and older. Pharmacological treatment is indicated if the 10-year probability of hip fracture is >= 3% or the 10-year probability of major osteoporotic fracture is >= 20%.
• CHA2DS2-VASc Score: Stratifies stroke risk in patients with non-valvular atrial fibrillation to guide oral anticoagulation therapy. A score of 2 or more in men, or 3 or more in women, strongly recommends oral anticoagulation (apixaban, warfarin) over antiplatelet therapy.
• STEADI Framework (CDC): Fall risk assessment tool used annually for older adults (>= 65). It screens with three questions regarding past falls, unsteadiness, and fear of falling. If positive, physical tests like the Timed Up and Go (TUG) are performed to determine safety interventions.

Risk Stratification Tools and Thresholds

Clinical Traps

• Statin Monotherapy Decisions: Initiating statin therapy based solely on isolated LDL cholesterol levels without calculating the comprehensive ASCVD 10-year risk score (unless LDL is >= 190 mg/dL, which is an automatic trigger for high-intensity statin).
• Gender Bias in Osteoporosis Screening: Failing to assess osteoporosis and fracture risk in older men. While screening bone density (DEXA scan) universally starts at age 65 for women, men aged 70 and older (or 50–69 with risk factors like chronic steroid use) should undergo FRAX assessment.

Worked Scenario

A 62-year-old male presents for a wellness visit. He has a history of controlled hypertension, a BMI of 28.5 kg/m², and a family history of a father who died of a myocardial infarction at age 52 (premature ASCVD). His lipid panel reveals a total cholesterol of 210 mg/dL, HDL of 38 mg/dL, and LDL of 132 mg/dL. He does not have diabetes and is a non-smoker. The FNP calculates his 10-year ASCVD risk score, which is 11.8% (intermediate risk). Because his risk is intermediate and he has a significant family history of premature ASCVD (a risk-enhancing factor), the FNP initiates a patient-clinician discussion. Based on ACC/AHA guidelines, they decide to start a moderate-intensity statin (atorvastatin 20 mg daily) with a goal to reduce LDL by 30% to 49%. The FNP also provides behavioral counseling to address his sedentary lifestyle and schedules a follow-up lipid panel in 4 to 12 weeks to assess efficacy.