Evolution of multimorbidity in a patient over time across three domains
| Domain | Age, years | Clinical picture |
|---|---|---|
| 1a. ORDERED Simple system • System characteristics: there is a simple, known, or knowable relationship between cause and effect. • System approach:6 sense, categorise, respond. | 30 | • Patient develops dyspepsia. Treated with antacids Simple system |
| 1b. ORDERED Complicated system • System characteristics: the system can be considered as a number of simple systems that do not interact. • System approach:6 sense, categorise, respond. | 40 | • Worsening dyspepsia treated with proton pump inhibitors • Develops gout. Started on allopurinol • Found to have essential hypertension, controlled with an angiotensin-converting enzyme (ACE) inhibitor |
| 2. TRANSITIONAL • System characteristics: although exact causal relationships cannot be known, the direction in which variables drive the system can reasonably be assumed. • System approach:6 sense, analyse, respond. | 50 | • Due to stress at work, restarts smoking • Develops ischaemic heart disease against a background of a positive family history • Lack of exercise leads to increased weight • Increased weight and smoking exacerbates dyspepsia • Develops peripheral vascular disease |
| 3a. UNORDERED Complex system • System characteristics: causal relations not clear but patterns emerge that can be identified in retrospect. • System approach:6 probe, sense, respond. | 55 | • Poor sleep exacerbated by obstructed sleep apnoea against background of obesity • Becomes depressed • Starts drinking 40 units of alcohol a week • Loses job and family splits up |
| 3b. UNORDERED Chaotic system • System characteristics: unstructured randomness. • System approach:6 sense, stabilise. | 60 | • Loses home • Drinking increases • Non-compliant with medication • Self-harm attempt |