Multimorbidity

So, how many times have elderly patients, as they leave my consulting room, offer me some advice? Well lots do actually, and invariably it’s the same advice, ‘Don’t get old doctor’! 

They are, I think, the unfortunate ones who are paying a price for living longer.  Increasingly common in number are patients carrying many diseases through their twilight years.  It can be a full-time job being an elderly patient coping with a long-term chronic disease.  There are so many medications to take, and the burden of living with chronic symptoms and their impact disability. This is the issue of age-related multimorbidity, a word we hear increasingly nowadays. 

Multimorbidity is the co-occurrence of multiple chronic or acute diseases and medical conditions within one person. For example, diabetes, osteoarthritis, partial loss of eyesight, atrial fibrillation, osteoporosis and diverticular disease – here all chronic conditions - might all exist quite typically in any given 75-year old (say). Multimorbidity does not necessarily mean someone is ‘super-ill’; indeed, each condition may be ‘under control’ as a result of regularly-taken medications or specific therapeutic measures or in partial remission. However, the conditions are there, ever present, as potential problems, permanently on the medical record. The more conditions you have the harder you and your doctor have to work to keep you healthy, to monitor the conditions, to review and update your medications to prevent worsening of any single condition, and to monitor for bad effects of the medications too – all to keep you on the healthy straight and narrow. 

As we get older, the risk of developing more conditions invariably increases – for various reasons but not least because many conditions have a strong association with ageing. I have looked after patients with staggering number of conditions too many times to recall; sometimes 10-20 separate conditions. Such multimorbidity can mean the last years of life can be pretty miserable. And average life-span is increasing so carrying more and more conditions as a general phenomenon will get more common, particularly as treatments improve at temporising / partially treating conditions.

Musculoskeletal (MSK) multimorbidity is especially complex. Very often one condition influences and affects another, invariably making it worse. Illness can spiral and unravelling it can be difficult. For example here is a not unusual ‘portfolio’ of 10 musculoskeletal multi- or comorbidities an individual may be carrying through their last few years, say at the age of 75-80 years. The presence of chronic pain throughout is a regular common finding and conditions can add up to provide a burden of chronic pain. The inter-influence / inter-dependence of conditions is illustrated by underlining: 

  • Osteoarthritis of one or a number of joints (indeed ‘general osteoarthritis – somewhat genetically determined is not a rare condition) causing chronic pain, and contributing to back pain (in facet joints) and causing disability through reduced functioning/movement;

  • Osteoporosis/fractures. Osteoporosis is highly associated with the likelihood of fragility fractures, which may be frequent, and with consequences of chronic pain, deformities and decreased independence of living;

  • Chronic kidney disease (CKD) stage 3b or higher (contributing to fatigue, anemia, ischaemic heart disease risk, bone disease including osteoporosis and joint disease such as CPPD); 

  • Calcium-crystal induced arthritis such as calcium pyrophosphate dihydrate (CPPD), which can cause either episodic or chronic joint pains and swelling, and it is associated with primary hyperparathyroidism (PHPT) – see below; 

  • Sarcopenia (general muscle weakness with poor function) causing imbalance, poor confidence walking and contributing to falls risk – thus increasing osteoporotic fragility fracture likelihood after a fall. It is made worse by vitamin-D deficiency and inactivity, which is itself often a consequence of chronic pain; 

  • Intervertebral degenerative disc disease – usually in the lumbar spine causing chronic pain and stiffness, contributing to poor core muscle stability/sarcopenia, compromising mobility and increasing falls risk;

  • Lumbar spinal stenosis, which is bone and thickened ligament flavum ‘crowding’ the spinal canal constricting the lumbar spinal nerves and reducing their function ultimately causing chronic back and leg pain, leg weakness and lack of mobility. It is often caused by facet joint osteoarthritis in the spine;

  • Vitamin-D deficiency contributing to weak muscles/sarcopenia and bone loss – the latter through subsequent calcium lack and secondary hyperparathyroidism, which increases fracture risk and aggravates osteoporosis;

  • Rotator cuff disease (RCD). This is where age, time, a lifetime of use and injury contribute to the wearing away and tearing of the supraspinatus tendon that controls the arm at the shoulder as it is raised and rotated. The condition may be caused/contributed to by osteoarthritis of the acromioclavicular joint as well.  Tears of the tendon accelerate the path toward whole shoulder joint osteoarthritis. The effect of RCD is to limit arm use, cause chronic pain and lead to disability reduced use of the arm;

  • Primary hyperparathyroidism (PHPT), a hormonal condition, present in about 1 in 70 people over the age of 50 years old but increasing in frequency with age over 50 years, which can cause fatigue, joint and muscle aches and osteoporosis and affect heart, kidney and gastrointestinal function. PHPT increases the risk of having CPPD. PHPT is made worse in certain instances by vitamin D deficiency.

Yes quite!! Furthermore, as specialists, rheumatologists might very often be considering all this for an elderly person who has been referred to them by their GP for a totally different problem altogether such as inflammatory arthritis, or polymyalgia rheumatica or some autoinflammatory or autoimmune condition!

So where do we start?

Treating any one condition in an older person in the context of all these MSK relevant interconnecting multimorbidity and their treatments becomes a complex matter, the success of which is often blunted because of the risk of, or contraindications to, medicines because of risky drug interactions or side-effects, or in the case of considering operations (e.g. joint replacement surgery or parathyroidectomy), too much risk of undertaking the operation. If someone is taking numerous medications it’s called ‘polypharmacy’, which can be considered itself to be a condition. The more medications are being prescribed the more likely there are drug interactions or side-effects and the greater the risk of non-adherence (meaning the medicine is not taken as often as is prescribed but also not taking them in the correct way when they are taken). Its stating the obvious but not taking a medication at all or incorrectly is the best way of making it unsuccessful!

Curing all these conditions for someone is impossible. Those of you ahead of me here, are saying “prevent”. It’s a good place to start of course, and many of these conditions can be prevented by finding solutions based in adherence to good public health behaviours – avoid smoking (which we know increases the risk of osteoporosis, vitamin D deficiency and can worsen effects of CKD, sarcopenia and osteoarthritis), avoid obesity (which drives the deterioration of knee osteoarthritis, provides an increased risk of vitamin D deficiency and worsens spinal stenosis), avoid inactivity (which hastens sarcopenia and increases bone loss [osteoporosis]). So….. self-care, self-responsibility – it’s an essential start.

Healthcare systems should also play a key role in prevention too though, not least addressing the persistent blight of delayed and/or wrong diagnosis which prevents an accurate and potentially successful therapy (/prevention) plan to be offered and initiated. In almost all instances early diagnosis leads to better outcomes – however these are judged. But so many times simple MSK conditions are overlooked, not diagnosed, misdiagnosed or diagnosed late. A simple condition may then become a complex one, or a curable condition becomes a chronic disease. Then of course is the added burden of the condition – accruing multimorbidity. 

Both individuals and Healthcare systems need to grasp the nettle of taking meaningful steps to avoid accumulating MSK multimorbidity. The first step in doing this though is surely understanding the number and burden of individual conditions that occur and their inter-influence / interdependence. The second step is the job of Healthcare systems not to ignore conditions, to diagnose them early and accurately and to think about taking measures to prevent or minimise disease long before the twilight years (‘the multimorbidity years’) arrive.

See also: https://www.nice.org.uk/guidance/ng56/chapter/Recommendations#multimorbidity