Pack Years Calculator for Smoking History
Quantifies cumulative tobacco exposure. One pack year equals 20 cigarettes per day for 1 year. Used in lung cancer risk assessment, COPD staging, and LDCT lung cancer screening eligibility. NICE DG44 recommends LDCT for adults aged 55-74 with 20 or more pack years who are current or ex-smokers.
Score interpretation
Light cumulative tobacco exposure
→ Smoking cessation counselling and NRT if current smoker; spirometry if symptomatic; standard cancer screening.
Moderate cumulative exposure -- COPD and cancer risk elevated
→ Smoking cessation intervention; spirometry for COPD assessment; consider LDCT if aged 55 or above (NICE DG44 threshold is 20 pack years -- this patient is just below threshold); cardiovascular risk assessment.
High cumulative exposure -- significant lung cancer and COPD risk
→ LDCT lung cancer screening eligibility met if aged 55-74 (NICE DG44); refer to lung health check programme if available; spirometry with bronchodilator reversibility; intensive smoking cessation; chest X-ray if not recently done.
Very high cumulative exposure -- highest lung cancer and COPD risk tier
→ Urgent LDCT screening if not done; COPD likely -- spirometry and GOLD staging; intensive smoking cessation; annual respiratory review; cardiovascular risk reduction.
Interpretation bands for the Pack Years. Apply clinical judgement and local guidance.
References
- NICE Diagnostics Guidance 44 (DG44). Lung cancer: LDCT screening in adults aged 55-74 at higher risk. NICE. 2023.
- Global Initiative for Chronic Obstructive Lung Disease (GOLD). Global Strategy for COPD. 2024.
Related
Curated clinical cross-links plus same-class fallbacks.
- Major Haemorrhage / Massive Transfusion · BCSH; RCOA; RCEM; RCS — BCSH Guidelines
- Anaemia Investigation · BSH / NICE
- Splenomegaly Workup · BSH; BMJ Best Practice
- Deep Vein Thrombosis Diagnosis and Treatment · NICE CG144 / NICE NG158
- Sickle Cell Crisis · BSH 2021 / BCSH
- Neutropenic Sepsis · NICE CG151 2012 / ESMO
Decision support only — verify against a current formulary, NICE, or your local guideline before clinical use.