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destruction of pancreatic β-cells; and type 2 diabetes
mellitus (T2DM) caused by insulin resistance or im-
paired insulin secretion. T2DM is the most prevalent
form of diabetes, patients are more likely to usually
develop diabetic ketoacidosis (4) and damage can
occur to tiny blood vessels and nerves. For patients
with T2DM, the duration of the disease influences the
severity of diabetic neuropathy, increasing activity
limitations (5). In addition, patients are more likely
to develop cardiovascular and Alzheimer’s disease,
as well as various cancers (1). T2DM is a chronic
disease, exerting an adverse influence on the daily life
of patients and imposing a burden on their finances.
Therefore, great emphasis should be placed on disease
nursing for patients with diabetes.
Tai chi (also known as tai ji or tai chi quan), origi-
nating from ancient China, is a mind-body exercise
characterized by mild or moderate aerobic activity.
It is also an effective muscle strength training for the
upper and lower extremities. Tai chi is currently often
recognized as a physical fitness technique in our so-
ciety, especially for middle-aged or elderly people (6).
There are several styles of tai chi; Yang, Chen, Sun and
Wu styles are commonly practiced in daily life, and
the Yang style is the most popular among the public,
while the Chen style is viewed as the oldest (7). The
Yang style is typical of its concise movement, while the
Wu style is more notable for gentle action. Movement
in the Chen style varies during the whole process,
while the Sun style is well known for coherence (8).
However, different types of tai chi have a common
method. All of the styles involve continuous, gentle
and slow movements involving balance, strengthening,
breath control, mental concentration and relaxation (9).
Tai chi can therefore play a role in both physical and
mental rehabilitation. Some studies have suggested that
tai chi has favourable effects on a variety of factors,
including cardiovascular protection (10), fall preven-
tion (11), balance (12), flexibility (13), depression (14)
and quality of life (QoL) (15). Tai chi has potential
benefits in treating different diseases, including chro-
nic obstructive pulmonary disease (16), Parkinson’s
disease (17), osteoarthritis (18) and stroke (19). Thus,
tai chi may be a suitable exercise for individuals with
chronic diseases (9, 20).
Compared with pharmacological therapy, tai chi is
an economical treatment, and can be performed where-
ver convenient, and is less likely to result in adverse
effects (21). As a mind-body exercise, tai chi may
have effects on both physical and mental well-being.
Individuals who perform tai chi are reported to tend to
have better psychological health (7). Given the above
strengths, tai chi may be a suitable complementary
treatment for patients with T2DM; thus it is critical to
www.medicaljournals.se/jrm
elucidate its effects on such patients. Although some
systematic reviews (22–25) have been performed to
evaluate the effectiveness of tai chi for patients with
T2DM, no definite conclusions have been drawn.
First, discrepancies existed in the conclusions of those
reviews. Lee et al. (22), Yan et al. (23) and Lee et al.
(24) reported that tai chi did not reduce fasting plasma
glucose (FPG), glycosylated haemoglobin (HbA1c), or
insulin resistance (IR), and they did not find that tai
chi was an effective rehabilitation therapy for T2DM.
On the other hand, Huang & Yeh (25) indicated that
tai chi was effective in improving HbA1c and FPG.
Furthermore, it is inappropriate for some reviews (23,
24) to combine data from studies with different designs
or methods, as this might lead to high heterogeneity.
In addition, since these reviews were published a long
time ago, the evidence should be updated.
For some patients with T2DM, the main pathological
change is IR, which in turn contributes to the high con-
centration of fasting insulin (FIN) in peripheral blood.
Therefore, FIN may be regarded as a medical indicator
reflecting IR to a certain degree. Patients with T2DM
are more vulnerable to diabetic neuropathy, foot ulcera-
tion and nerve damage due to infection (26). Postural
instability, which is common in diabetic sensory neuro-
pathy, could increase the risk of minor foot trauma (27).
Improvement in stability is a prerequisite for normal
physical activity. Moreover, patients with T2DM are
under great pressure to treat themselves, and they usu-
ally have lower QoL compared with healthy individuals
(28). QoL is one of the comprehensive indicators for
evaluating self-management of disease and therapeutic
effects, and thus QoL may be an appropriate target for
treatments in patients with T2DM. However, whether
tai chi training could improve these outcomes remains
controversial, and no relevant content was reported in
the above reviews.
The objective of this review was therefore to syn-
thesize and critically evaluate the published evidence
on the effects of tai chi on FPG, HbA1c, IR, FIN, body
mass index (BMI), total cholesterol (TC), blood pressure
(BP), balance and QoL among individuals with T2DM.
METHODS
Data sources
Seven electronic databases (Wan Fang, SinoMed, China Na-
tional Knowledge Infrastructure, VIP, PubMed, Embase, and
Cochrane Library) were searched for eligible publications from
their inception to March 2018. The following search terms were
used: “tai ji”, “tai ji quan”, “tai chi”, “tai chi chuan”, “type 2
diabetes mellitus”, “noninsulin-dependent diabetes”, “maturity-
onset diabetes”. Variations and synonyms of these search terms
were used in order to perform an overall and systematic search.
In addition, the reference lists of all related literature were